Tender leftover steak becomes this steak marinara freezer meal every time we have extra from dinner — 4.5g net carbs and 17g protein. Slice, bag, freeze, then cook it in the Instant Pot or on the stovetop for a fast keto dinner.
I started making this steak marinara after a night where I had half a pound of leftover ribeye and zero motivation to cook something new. Five minutes of slicing and bagging, and I had a freezer meal ready for the following week. That was three years ago, and I still make a batch every time we have steak for dinner.
The concept is dead simple. Take your leftover steak (any cut works, though I get the best results with flank and sirloin), slice it thin against the grain, and toss it into a freezer bag with marinara, diced tomatoes, spinach, and Italian seasoning. Seal it flat, freeze it, and you have a keto dinner that goes from freezer to table in under 30 minutes. I keep two or three bags in rotation at all times.
What sets this apart from just reheating leftover steak is the sauce. The marinara breaks down into the meat during pressure cooking, and every slice absorbs that rich, tangy tomato flavor. The spinach wilts to practically nothing, which is exactly why I load the bag with two full cups. You get the nutrition without the bulk. If you like my Instant Pot Swiss Steak, you will love how this comes together the same way.
I have made this both from thawed and from frozen. Thawed is faster (7 minutes on high pressure), but frozen works if you add 1/4 cup of water to the liner so nothing scorches. I learned that the hard way. No pressure cooker? The stovetop method is just as good. Thaw the bag overnight, dump it in a skillet, and heat until the sauce is bubbling. It is the same kind of weeknight dinner as my Keto Philly Cheesesteak, just with an Italian spin.
One thing I picked up from a reader: portion into single-serving bags before you freeze. I used to freeze one giant batch and then hack at a frozen block trying to get one plate out. Smaller bags mean you thaw only what you need for one meal. Same cook time, zero waste.
Pour it over cauliflower rice, hearts of palm noodles, or low carb pasta and it is a full dinner. My husband does not even ask what is in it anymore. He just eats it. If you are looking for more Instant Pot meals like this, my Keto Hamburger Helper is another one I keep in the regular rotation.
What to do with leftover steak
I am always looking for ways to turn leftover steak into something that feels like a brand new meal. My family does not want the same dinner twice in a row, and neither do I. This recipe is my answer. Slice up whatever you have left from last night, toss it in a bag with sauce and seasonings, and it transforms into a completely different dish. I have used ribeye, flank, sirloin, even the last few slices of a New York strip. They all work.
How to meal prep freezer meals
One of the things that keeps me consistent on keto is having meals ready to go when I do not feel like cooking. This recipe is perfect for that. On a night when you already have steak for dinner, slice up the extra, bag it with the rest of the ingredients, and stash it in the freezer. You are not adding any extra work to your evening. You are just not wasting what you already cooked.
I portion mine into individual bags now. A reader tipped me off to this, and it changed everything. Instead of freezing one massive batch and wrestling with a frozen block later, each bag is one dinner. Thaw what you need, leave the rest frozen. If you do a lot of batch cooking, my Keto Chicken Casserole is another recipe I prep and freeze the same way.
For an easy way to fill your freezer bags without spilling, use freezer bag holders to keep the bag upright while you add ingredients.
Choosing the right marinara sauce
You have two options here. A store-bought low-carb marinara or plain canned tomato sauce. Either works, but check the label for added sugars. Some brands sneak in 8-10 grams of sugar per serving, which defeats the purpose.
My go-to is Rao’s marinara. I use their sensitive formula, which skips the garlic and onion for people with digestive issues. Only 5 grams net carbs per half cup. If you are making Italian-style dinners regularly (like my Creamy Keto Tuscan Chicken), keeping a jar of Rao’s on hand is a baseline move.
Stovetop method
No Instant Pot? Not a problem. I make this on the stovetop just as often. Thaw the bag overnight in the fridge, then dump everything into a skillet over medium-high heat. Once the sauce is bubbling and the steak is heated through, you are done. Takes about 10 minutes. I use the same skillet approach for my Keto Skillet Meatballs when I want something fast without dragging out the pressure cooker.
Low carb pasta and noodle options
This steak marinara is begging to be poured over something. I rotate between a few options depending on what I have in the pantry:
Cauliflower rice is the easiest default. Five minutes in the microwave and you have a base.
Hearts of palm noodles are my current favorite for a low carb pasta swap. No weird smell, no rubbery chew, and they hold the sauce well.
Shirataki noodles work if you rinse them well first. They are zero carbs, made from konjac yam, and mostly water and fiber.
Low carb wheat pasta from The Great Low Carb Bread Company is what I reach for when I want the real noodle texture. Not gluten-free, but it is the closest to traditional pasta I have found.
Add all the ingredients to a gallon sized freezer bag.
2
Freeze
Press all the air out of the bag and seal. Store flat in the freezer until ready to cook.
3
Pressure cook
To prepare, thaw in the refrigerator the night before. Add all ingredients to the liner of an instant pot. Attach the lid and set the vent to seal. Pressure cook on high for 7 minutes. Release pressure by turning the knob to venting. If cooking from frozen, add 1/4 cup of water to the liner of the instant pot along with the ingredients to prevent the contents from burning.
4
Serve
Pour steak marinara over low-carb noodles or cauliflower rice.
Nutrition
Calories
231
Fat
15.1g
Protein
17g
Total carbs
6.3g
Net carbs
4.5g
Nutrition is an estimate calculated from the ingredients listed. Brands vary, so check labels if you track closely.
Frequently Asked Questions
Can I use raw steak instead of leftover steak?
I have done it both ways. With raw steak, you need to increase the Instant Pot time to about 12-15 minutes on high pressure depending on thickness. I slice it thin (about 1/4 inch) so it cooks evenly. The texture is slightly different since raw steak firms up more during pressure cooking, but the flavor is just as good. My preference is still leftover steak because the pre-cooking gives it a better chew in the finished dish.
Should I portion into individual bags before freezing?
This is something I started doing after a reader mentioned it, and I will never go back to the big-batch method. I portion everything into single-serving freezer bags before they go in the freezer. That way I only thaw what I need for one dinner. Same cook time, no waste, and no hacking at a frozen block with a knife.
Does the spinach disappear into the sauce?
Pretty much, yes. I load in two full cups of fresh baby spinach and it wilts down to almost nothing during cooking. That is actually why I go heavy on it. You get the nutrition without changing the texture or flavor of the dish. If you want even more greens, you could easily add an extra cup and not notice a difference.
What cut of steak works best for this recipe?
I have tested this with ribeye, flank, sirloin, and New York strip. They all work. Flank is my top pick because the thinner slices soak up the marinara better during pressure cooking. A reader confirmed the same thing with leftover flank from taco night. Ribeye is richer but can get a little soft. Sirloin is a solid middle ground if you want something leaner.
Can I add mushrooms or other vegetables?
I have thrown in sliced mushrooms and they basically vanish into the sauce, which is a great trick if someone in your house claims they do not like mushrooms. A reader added them to stretch the recipe to five servings without changing the Instant Pot cook time at all. I would keep additions to things that cook quickly at the same rate: bell peppers, zucchini, or diced onion work well.
How long does this keep in the freezer?
I have pulled bags out after two to three months and they tasted exactly the same as week-old ones. Seal the bag flat with as much air pressed out as possible and it stores well. In the fridge, my leftovers keep for three to four days in an airtight container.
What can I use instead of store-bought marinara sauce?
I keep Rao's on hand most of the time, but when I run out I make a simple sauce from canned crushed tomatoes, dried Italian herbs, a little garlic, and salt. It takes about five minutes on the stove. The key is checking the sugar content on whatever brand you grab. Some jarred sauces sneak in 8-10 grams of sugar per serving, and that adds up fast on keto.
Do I need to thaw the bag first or does it go in the Instant Pot frozen? I’m nervous about the steak getting tough. Annie your recipes have been getting me through the week.
Thanks Elizabeth. I thaw mine in the fridge overnight. The steak is already cooked, so it’s just heating through in the sauce and won’t toughen up on you.
I’m normally the one rationing freezer meals to make them last, but my husband started pulling these out himself. Now I just make more. The steak doesn’t taste like leftovers once the sauce works through it, more like it was supposed to cook that way.
Usually I’d say freezer dump meals trade quality for convenience, but the steak here absorbs the marinara and comes out more tender than it went in. Most leftover-steak methods can’t pull that off. Runs mild as written, though. Red pepper flakes from the start would help.
Katie, red pepper flakes in the bag is a good call. I’d go a half teaspoon so it spreads through the sauce while it sits in the freezer. I’m trying that next batch.
Drain the diced tomatoes before they go in the bag. First time the sauce ran thin and that was why. Added a tablespoon of tomato paste on the second batch and it was totally different, thick and red, coating every piece of steak. Worth the fix.
Draining is the right call. I started doing the same after my first batch came out watery, and that tablespoon of tomato paste is what gets the sauce to actually coat. Smart fix, Camila.
We’ve been doing a big freezer meal push this summer (anything to avoid turning the oven on) and this steak marinara is going in the rotation. Planning to make four or five bags at once this weekend. When I thaw each one and cook it in the Instant Pot, does the pressure cook time stay the same per bag, or does it change depending on how thawed each bag is? I’ve had other IP recipes get finicky when I batch-prepped them.
Chris, cook time stays the same. Frozen bags take longer to come to pressure, which is where IP recipes get finicky, but once you’re there the timing holds. I’ve done everything from fully frozen to barely chilled and haven’t had to adjust.
The sauce gets this deep tomato flavor once the steak releases its juices into it, which I didn’t fully appreciate until I brought a batch to a friend’s birthday dinner and two people asked what I’d added to the marinara. Nothing extra, it turns out. Plated over zucchini noodles with some parmesan, it looked like more work than dumping a freezer bag into the Instant Pot. Keeping a few bags stocked at all times now.
The steak does all of it once the juices go in. Took me a while to stop adding things and just trust that. Zucchini noodles with some parmesan on top and nobody at the table thinks freezer meal.
First freezer dump bag I’ve actually committed to, and I went stovetop instead of Instant Pot. Pulled it from the fridge after an overnight thaw, got the garlic paste blooming in oil first before adding everything else. Used Primal Kitchen marinara because that was open. Had real doubt about whether pre-cooked steak would hold up or go rubbery, but it came out tender. Actually shocked me. Spinach looked like way too much going into the bag but folded down to almost nothing once it hit the pan. Two more bags in the freezer already.
Garlic paste bloomed in oil first is the right call, the sauce picks up that depth before anything else dilutes it. Primal Kitchen is solid for this. Two bags in the freezer means dinner is actually handled.
Arrabbiata in this makes sense. The heat cuts through the fat and you end up with something that actually stands on its own instead of tasting like leftovers.
Swapped the spinach for mushrooms because I was completely out, and they basically melted into the marinara and made everything richer somehow. Ate it straight from the Instant Pot insert, didn’t regret a thing. Didn’t even bother with noodles. Making this again Friday with double the garlic.
We do big steaks on the weekend pretty regularly, so there’s almost always extra. Started using the leftovers for this a few months back and now I actually look forward to having extra on purpose. The Instant Pot version is what sold me. Spinach wilts right into the sauce and it comes together like it’s been simmering for hours, not 10 minutes from frozen. Cauliflower rice underneath and it doesn’t feel like a leftover meal at all.
The Instant Pot from frozen version is the one I make most. That 10 minutes feels impossible but it works. Cauliflower rice underneath is what I do too.
My mom used to throw together something close to this on busy weeknights, over regular pasta with jarred sauce. I made this version last week with leftover ribeye from Sunday and when it started warming up in the Instant Pot, the smell hit me out of nowhere. I wasn’t expecting to get sentimental over a freezer meal. The marinara with the spinach and garlic paste tastes like something I grew up eating. Going to keep this in the rotation.
Ribeye fat does something to the marinara that flank doesn’t. Sauce comes out richer. And the garlic paste smell when that lid pops (yeah, every time).
I’ve never done a freezer meal before, and I picked this one because I had leftover steak and zero plan for it. Threw everything in the bag Sunday night, cooked it Thursday in the Instant Pot, and the steak came out freaking tender. Doing this every single time we grill now.
If you press the bag completely flat before freezing it stacks perfectly in the back of your freezer, which sounds obvious but I never figured that out until this recipe. Pulled one out last week when I had nothing planned and it was on the table in like 20 minutes.
20 minutes on a nothing-planned night is the whole reason I make this in batches. And yeah, the flat bag thing took me embarrassingly long to figure out.
Before keto, Sunday marinara was my whole thing. Made this over cauliflower rice last week and that tomato and garlic smell from the Instant Pot brought everything back. I did not realize how much I had missed it until I was eating it again.
The Instant Pot timing is spot on, the steak came out falling apart tender instead of the chewy texture I was bracing for from reheated leftovers. My one note: a cup of marinara gets thin fast over cauliflower rice, so I’ll use 1.5 next time. Otherwise, this is locked in.
I had leftover sirloin from dinner and genuinely wasn’t sure it would hold up in the Instant Pot (usually that kind of thing comes out grainy and sad), but I had everything else already and figured worst case I’d just eat it anyway. The steak was fine. More than fine. It softened into the marinara and the spinach cooked down like it had been going for hours. It hadn’t. Cold night in February. Exactly what I needed.
