Keto Chocolate Lava Cake
Published January 25, 2021 • Updated February 27, 2026
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I make this keto chocolate lava cake in the microwave in 2 minutes, and the center comes out molten every time. Top with whipped cream or sugar-free ice cream and let the warm chocolate do the rest.
I’ve been making this chocolate lava cake for years, and it’s the dessert I come back to when I want something that feels indulgent without the sugar. The whole thing takes about 5 minutes from bowl to plate, and the center comes out molten and gooey every single time.
What makes this version different is the technique. Instead of using a water bath like traditional recipes, I drizzle a tablespoon of water right on top before microwaving. That water creates steam inside the dish, which melts the sugar-free chocolate without overcooking the cake around it. I figured this out after burning through a few batches trying to get the timing right, and once I landed on this method, I never went back.
The batter itself is simple: almond flour, cocoa powder, butter, heavy cream, and an egg. I use a monk fruit blend sweetener, but I’ve tested it with erythritol and allulose too (more on that in the FAQs below). The key is getting everything mixed in one bowl and poured into a greased 4.5-inch glass dish before topping with broken pieces of sugar-free chocolate.
Two minutes in the microwave and the edges set up while the center stays soft. Let it rest for 4-5 minutes (this part matters, don’t skip it), then flip it onto a plate. The melted chocolate ends up on top, pooling into the center. That first fork-pull where the chocolate oozes out is the whole point.
If you love chocolate desserts, I have a few others worth trying. My keto chocolate mug cake and chocolate chip mug cake are other fast options when you want something in minutes. For a different texture, my easy keto chocolate cake bakes up light and fluffy. And if you want something no-bake, my keto fudge scratches that rich chocolate itch without turning on the oven.
I top mine with sugar-free whipped cream and let it melt into the warm cake. A scoop of sugar-free ice cream works too. As the cold cream hits the hot chocolate, it creates this contrast that makes the whole thing feel like a real dessert, not a ‘keto dessert.’
One thing I’ll be upfront about: you can’t make this ahead. The molten center is the entire point, and once it cools and sets, reheating doesn’t bring it back. But since the whole recipe takes 5 minutes, that’s never felt like a real problem to me.
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Ingredients
1/3 cup almond flour -
2 tablespoons monk fruit blend sweetener
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2 tablespoons unsweetened cocoa powder
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1/2 teaspoon baking powder
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pinch of salt
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3 tablespoons unsalted butter, melted
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3 tablespoons heavy cream
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1 egg
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1/2 teaspoon vanilla
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1 oz sugar free chocolate
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1 tablespoon water
Step by Step Instructions
Step by Step Instructions
Get a small bowl
In a small bowl, whisk together almond flour, sweetener, cocoa powder, baking powder and salt.
Pour batter
Pour cake batter into a greased microwave safe round dish (about 4.5 inches in diameter).
Top it
Top with broken pieces of chocolate. Drizzle water on top. Microwave on high for 2 minutes or until edges of the cake are set. The center will be tacky and moist to the touch.
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
What sweetener works best for this recipe?
I developed this recipe with a monk fruit blend sweetener, and that's what I'd recommend first. I've also tested it with erythritol and allulose. Erythritol works fine but make sure you use the powdered version, not granular, or you'll get a slightly grainy texture in the cake. Allulose gives a softer, spongier crumb which I actually like for this recipe, but it browns faster so keep an eye on it. If you use stevia, start with half the amount and taste the batter before cooking.
Can I use coconut flour instead of almond flour?
I've made this with coconut flour when I ran out of almond flour, and it works, but you need to use about a quarter of the amount. Coconut flour absorbs way more liquid, so if you use the same quantity you'll end up with something closer to a hockey puck. Start with about 1.5 tablespoons of coconut flour in place of the 1/3 cup almond flour, and add an extra tablespoon of heavy cream to keep the batter loose enough.
Can I make this ahead of time or freeze it?
I've tried both, and my honest answer is no, not once it's cooked. The molten center is the whole point of this dessert, and once it sets, reheating doesn't bring it back. But I have refrigerated the raw batter overnight and cooked it fresh the next day, and that actually works. Mix everything up, pour it into your dish, cover it, and refrigerate. When you're ready, add the chocolate and water on top and microwave as usual, adding about 15-20 extra seconds since the batter is cold.
Can I make this dairy-free?
I've swapped the butter for coconut oil and the heavy cream for coconut cream, and it comes out great. The coconut oil gives it a slightly different flavor that I actually enjoy with the dark chocolate. Use the same amounts as the original recipe. Just make sure your coconut cream is the thick stuff from the top of the can, not the watery liquid underneath.
My microwave runs hot or cold. How do I adjust the cook time?
Microwave wattage makes a bigger difference than most people realize. My microwave is about 1100 watts, and 2 minutes is perfect. If yours is lower (around 800 watts), start with 2 minutes and 30 seconds. If yours runs hot, try 1 minute and 45 seconds. The edges should be set and slightly pulling away from the dish, but the center will still look wet and jiggly. I'd rather undercook by 10 seconds and add more time than overcook and lose the molten center.
How do I know when it's done if the center is supposed to be underdone?
This tripped me up at first too. The edges are your indicator. They should look set and matte, not shiny. The center will be wet, shiny, and soft to the touch. If you press it gently, it should feel like touching the top of a marshmallow. If the center looks set and dry, it's overcooked and you won't get that oozy chocolate when you flip it. I always err on the side of pulling it early.
Is the undercooked center actually safe to eat?
I get this question a lot. The batter has one whole egg in it, and at 2 minutes in a standard microwave, the internal temperature reaches well above what's needed to fully cook the egg. I've checked with a thermometer. The chocolate melts at a much lower temperature, so the center can be gooey melted chocolate while the egg in the surrounding cake is fully cooked. The molten part is chocolate, not raw batter.
Can I make this in an air fryer?
I've tested this in my air fryer at 350 degrees for about 6-7 minutes, and it works well. Use an oven-safe ramekin that fits your air fryer basket. The air fryer gives you crispier edges than the microwave, which I love. Check it at 6 minutes and look for the same signs: edges set, center jiggly. Let it rest for 4-5 minutes before flipping.
The dish size matters more than the cook time, something I figured out after two batches that came out flat instead of molten. Once I switched to an actual 4.5-inch round dish, the batter depth was right and the center stayed soft the way it's supposed to. I also swapped in Lily's dark chocolate for the top layer and it melts into the center more cleanly than a standard bar. Small adjustments, but they fixed what I'd been doing wrong.
Dish size is the one I should have been clearer about. Most people grab a standard 6-ounce ramekin and the batter spreads too thin to hold the center.
Made these for a dinner party on Saturday and didn't say anything about them being keto. A couple of people asked what the molten center was made from before I mentioned the sugar-free chocolate. The 2-minute microwave timing made it easy to do individual portions right before we sat down, which I appreciated.
Ha, the center always gets people. That 2-minute window right before sitting down is why I love this one for company.
Used Lily's chips instead of a chocolate square and waited the full 5 minutes before inverting, and that center actually ran.
Lily's chips work? Good to know. They melt slower than a solid square so that extra wait probably helped keep the center loose.
Made this six times now and pulling it at 1:45 instead of 2 minutes gets way more molten center. That 15 seconds makes a real difference when you flip it. Still no idea why the water drizzle works but I've stopped questioning it.
1:45 is my starting point. The water traps steam and slows the center from setting - once I figured that out the rest clicks.
My sister is visiting this weekend and she's dairy-free, so I'd love to make this for her. I've swapped coconut cream for heavy cream before with good results, but the butter is trickier since the fat content matters so much for that molten center. Would refined coconut oil work as a 1:1 swap, or does the ratio need adjusting?
Yeah, same amounts. I've done the full swap (coconut oil for butter, coconut cream for heavy cream) and it works. Refined is the right call here, unrefined would add a coconut flavor on top of the dark chocolate.
Put your scientist hat on, please....the hubs is having some bad reactions to sweeteners, and because I have used several kinds and can't remember which I may have used in a particular recipe, do you have a recommendation for one that has the least side effects? He experiences a sore throat shortly after eating, and then gastro issues later. I'm guessing erythritol (swerve) is a culprit, but I've also used Allulose and a monk fruit/Allulose blend. Is it possible that all of them a problem?
It’s very possible all of those could be triggering him, but erythritol is the most likely culprit, especially with the immediate sore throat plus later GI issues. Allulose is usually better tolerated but can still cause digestive upset in some people. If you want the lowest-risk option to test, I’d try 100% allulose sweetener and see if his symptoms stop. Another option is 100% monkfruit sweetener (one that isn't mixed with erythritol or allulose).
Holy Moly, this is so amazingly good! You just made my life so much sweeter, thank you for your awesome recipes!
The 2-minute wait is the hardest part. I always add a pinch of flaky salt on top - cuts right through the sweetness.
I have not found a good small dessert that had the right texture until this - so rich!!! I only ate 1/4 and put it away as a treat to savor over several servings - especially with the homemade whipped cream. I used allulose and it was wonderful - thank you!!!!! Love your channel. Your recipes appeal to non-ketoers too!
Allulose works well here, texture stays softer than erythritol. The whipped cream is not optional in my house either.
This literally is my favorite quick dessert to make. So delicious and easy to make!
The molten center gets me every time. Flaky salt on top if you haven't tried it.
Instead of the monk fruit blend, can you substitute swerve for it in all of your dessert recipes?
Yes, you can!
Would like your 20 minute ice cream maker name and your ice cream recipe. I don’t have social media, but have seen your channel on UTube.
here's my ice cream recipe: https://www.ketofocus.com/recipes/keto-vanilla-ice-cream/
I just tried this. It's insanely delicious. I sure I'll be making this weekly. I miss chocolate donuts and this will solve that craving. Didn't have to alter the recipe at all. Thanks!
Chocolate donut craving solved. Try it with whipped cream on top next time, the cream melts right into the warm cake.
Delish!!!! Ok so I have been on keto for a cool minute; but, this cake is great!! It’s easy to make but for the topping I made a whipped cheesecake topping (I couldn’t help myself). I also sub substituted half of the sweetener in the cake for half of sugar-free vanilla syrup used in coffee‘s. I feel like I am sinning... but I am not!
Whipped cheesecake topping on a lava cake, yeah that's going on my list. Haven't tried swapping in vanilla syrup but if the center still ran you got it right.
This is so delicious!!! Loved every bite! Just a quick question. Are the macros above calculated per serving or for the entire thing?
Macros are for two servings. So if you ate it all, then you would double the macros. I split it into two because I felt like it was caloric dense for those watching calories.
Anne, I love your recipes and I follow you on YouTube. Keep up the good work ?
Thanks Steve! The lava cake is a good one to try if you haven't yet. Two minutes in the microwave and the center comes out molten every time.