Keto Grilled Foil Packet Asparagus
Published August 9, 2020 • Updated February 24, 2026
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I make grilled asparagus in foil all summer long. Toss the spears with olive oil, lemon juice, salt, and pepper, seal them in a foil packet, and grill for about 10 minutes. The cleanup is nothing, the flavor is everything, and at 3.5g net carbs per serving, this is my go-to keto side dish for any cookout.
I started making keto grilled asparagus in foil packets years ago because I was tired of spears falling through the grill grates. The foil solves that completely. You get tender, evenly cooked asparagus without losing a single spear to the coals, and cleanup is just crumpling up the foil and tossing it.
The method is simple. Toss a pound of asparagus with olive oil, salt, pepper, and a squeeze of fresh lemon, then seal it all in a foil packet with some room at the top. That air space matters. It lets the steam circulate so the spears cook evenly instead of getting mushy on the bottom and raw on top. I grill mine over direct heat for 5-8 minutes, and here is my favorite part: in the last minute, I open the packet and let the spears sit directly on the grate. You get those charred grill marks on asparagus that was already perfectly cooked inside the foil. Best of both worlds.
One thing I have learned after years of grilling this way: olive oil is the right fat here, not butter. Butter burns fast at grill temperatures, and it really falls apart once you open that foil for direct contact. Olive oil has a higher smoke point and holds up through the whole process. I finish with freshly grated parmesan after it comes off the grill, and that is where the richness comes in without the scorching risk. This low carb side dish pairs with just about anything off the grill. I serve it next to my grilled marinated chicken almost every weekend in the summer.
If you are working with thick asparagus spears (thicker than a pencil), give them an extra 2-3 minutes in the packet. Thin spears cook faster and can go limp if you leave them too long, so check at the 5-minute mark. I have made this with both, and honestly I prefer the thicker stalks for grilling because they hold up to the heat and have a meatier bite.
This works on a campfire too. I have made these packets on camping trips by setting them right on the grate over embers. Same timing, same result. And if the weather turns on you, the oven at 350 degrees is a solid backup. The closed oven environment traps moisture the same way the foil does, so the spears come out just as tender. They will not get grill marks, but the lemon-parmesan finish still makes them worth it.
For more asparagus options, I have an oven roasted asparagus recipe that is great for weeknights, and my air fryer asparagus gets crispy edges in under 10 minutes. If you want something more substantial, try my bacon wrapped asparagus kebabs on the grill. And if you are building a full cookout spread, my Traeger grilled vegetables, grilled pizza, and homemade keto BBQ sauce round things out nicely.
Ingredients
1 pound asparagus -
2-3 tablespoons olive oil
-
1/2 teaspoon salt
-
1/4 teaspoon black pepper
-
lemon juice squeeze from 1/2 lemon
-
1/4 cup grated parmesan cheese, optional
Step by Step Instructions
Step by Step Instructions
Trim asparagus
Preheat oven to 350 degrees or to medium high heat. Wash, trim and dry asparagus spears with a knife or snap them off.
Make a foil packet
Add asparagus to a sheet of foil. Drizzle olive oil, salt, pepper, and lemon juice. Press together edges of the foil to form a packet. Don’t press down the top of the foil to the asparagus. Leave space in between foil and asparagus to allow for even cooking.
Grill
Place the foil packet on the grill and cook over direct heat for 5-8 minutes, depending on the size of the spears, turning frequently. For grill marks, open the packet in the last minute and let the spears cook directly on the grate.
Nutrition disclaimer
The nutrition information provided is an estimate and is for informational purposes only. I am a Doctor of Pharmacy (Pharm.D.); however, this content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always consult your physician or other qualified health provider before making any lifestyle changes or beginning a new nutrition program.
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Get My Macros + Recipes →Frequently Asked Questions
Can I make this with garlic butter instead of olive oil?
I have tested both, and olive oil is my preference for this recipe. Butter burns at direct grill heat, especially once you open the foil packet for char marks. That said, if you want garlic butter flavor and plan to keep the packet sealed the whole time, it works. I melt 2 tablespoons of butter with a minced clove of garlic and toss the spears in that instead. Just skip the open-foil step at the end.
How do I know when the asparagus is done in the foil packet?
I check mine at the 5-minute mark by carefully opening one corner of the foil with tongs. What I am looking for is bright green color with just a slight give when I press a spear with the tongs. If the spears are still rigid and pale, they need another 2-3 minutes. If they are army green and floppy, they went too long. I have found that sweet spot is usually right around 6-7 minutes for medium-thickness spears.
Can I make this on a campfire instead of a grill?
I have made these on camping trips multiple times. Set the foil packet directly on the grate over hot embers (not open flames). The timing is about the same, 5-8 minutes, but I turn the packet more often since campfire heat is less even. I skip the open-foil step over a campfire because the heat is harder to control, but the asparagus still comes out great.
Can I cook this in the oven instead of on the grill?
I do this whenever it rains on my grilling plans. Preheat to 350 degrees and set the foil packet on a baking sheet. It takes about 12-15 minutes in the oven since the heat is less intense than direct flame. The closed oven environment traps moisture the same way the foil does, so the spears come out tender. You will not get grill marks, but the lemon and parmesan finish still carries the dish.
What's the difference between thick and thin asparagus for grilling?
I have grilled both plenty of times, and I actually prefer thick spears for foil packets. They hold up better to the heat and have a meatier texture when you bite into them. Thick spears (anything thicker than a pencil) need about 8 minutes in the packet. Thin spears cook in 5 minutes and can go mushy fast, so I watch those more carefully. Either way, the foil method works.
Should I use heavy-duty foil or regular foil?
I always use heavy-duty foil for grilling. Regular foil tears when I flip or move the packet, and one small rip means all the juices and steam escape. If you only have regular foil, I double up the layers. It is a small detail but it has saved me from losing packets through the grate more than once.
How do I get grill marks on foil packet asparagus?
This is my favorite trick. I cook the asparagus in the sealed packet for most of the time, then open the foil in the last 60 seconds and lay the spears directly on the grill grate. You get char marks on asparagus that is already perfectly tender from steaming. I use tongs to spread them out in a single layer so they all get contact with the grate.
Can I prep the foil packets ahead of time?
I do this for BBQs all the time. I assemble the packets up to 4 hours ahead, seasoning and all, and store them flat in the fridge. When the grill is hot, they go straight on. The only thing I wait on is the lemon squeeze, because I have noticed the acid makes the spears go soft if it sits too long. I add the lemon right before sealing if I am prepping ahead.
With asparagus in season, you don’t need to rely on mundane salads for a low carb side dish. This grilled asparagus is easy to make since you just wrap it in foil and toss it on your BBQ to cook. It also makes the perfect camping recipe when you want something quick. To prepare this keto side dish, all you need is asparagus, salt & pepper and olive oil. Add some lemon juice and parmesan cheese for a punchy, cheesy flavor.
I stopped making summer food when I started keto and I can't even explain why because asparagus was never the issue. Made this in the oven last night because I needed something that felt like July in February, foil packet and everything, and the parmesan melted into the lemon juice and olive oil in a way that just hit me. The spears came out tender with a little snap still in the thicker ones and I sat there thinking about every backyard cookout I'd written off for no reason. Going on permanent rotation until I can actually fire up the grill.
Made this in the oven on a Wednesday because we had asparagus that needed to go and my partner had come home already grumbling about the cold. I did the foil packet exactly as written and what I wasn't expecting is how the steam inside kind of does its own thing, there's this little pool of lemon and olive oil at the bottom when you open it and the spears come out tender but still firm enough to pick up. Added the parmesan at the end. My partner, who will slide vegetables to the side of the plate without saying a word about it, reached into the foil and took two more spears before I'd even moved it to a serving dish. That's the part that told me something was different here. I've made roasted asparagus probably fifty times and it's fine but it never provoked that. Something about the way the foil traps the lemon with the olive oil makes the whole thing more concentrated and a little brighter than plain roasting does. Planning to try it on the actual grill once it's not twenty degrees out.