Easy Keto Chocolate Chip Mug Cake in the Microwave
Published July 11, 2020 • Updated March 3, 2026
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I make this keto chocolate chip mug cake when I need something sweet in under two minutes. It tastes like a warm cookie fresh from the oven, not a spongy microwave cake, and the two-flour combo gives it that chewy center I spent weeks getting right.
I’ve been making this chocolate chip mug cake since I started testing single-serving keto desserts back in 2019, and it’s the one I come back to more than any other. Not because it’s the fanciest recipe on the site, but because it genuinely tastes like a warm chocolate chip cookie. That’s not marketing. Reader Alicia P. made it for her 8-year-old, and her daughter said it tastes “exactly like a cookie.” I know, because my boys say the same thing.
The secret is the two-flour combo. Most recipes like this use either almond flour or coconut flour. I use both. The almond flour gives you structure and that nutty richness, while a small amount of coconut flour absorbs excess moisture and creates the dense, chewy texture that separates this from spongy microwave bread. I tested it with almond flour alone and it was too loose. Coconut flour alone was too dry. Together, they just work.
The whole thing takes about 90 seconds of prep and 60-85 seconds in the microwave. I’ve tested this in three different microwaves and the sweet spot is around 70 seconds in a standard 1000W model. You want the top to look set but still slightly soft in the very center. It firms up as it cools. If you microwave it until it looks fully done, you’ll end up with rubber. Pull it early and trust the carryover.
I pour the batter into one large mug when I want a thick, gooey center, or split it between two smaller mugs when my kids both want one. Both ways work. Just make sure your mug is at least twice the volume of the batter because it rises fast and will overflow a small cup.
If you want more single-serving keto desserts, I have a whole collection. My chocolate version is rich and fudgy for when you want pure cocoa. The birthday version is what I make when someone in the house is celebrating and doesn’t want a full cake. The pecan pie version tastes like Thanksgiving in a cup. And if you want something totally different, the red velvet one has a similar texture with a completely different flavor.
This is a sugar-free dessert you can make without planning ahead, without preheating anything, and without dirtying more than one bowl and a mug. I keep all the dry ingredients in my pantry and can have it ready before the kettle boils. For a low carb treat that actually satisfies a real craving, this is what I reach for every time.
Ingredients
1 egg -
2 tablespoons almond flour
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2 tablespoons unsalted butter, melted
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1 1/2 tablespoons monkfruit sweetener or sweetener of choice
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1 tablespoon keto chocolate chips
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2 teaspoons coconut flour
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1/2 teaspoon baking powder
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1/4 teaspoon vanilla
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pinch of salt
Step by Step Instructions
Step by Step Instructions
Pour the batter
Pour mug cake batter in a large greased mug or into two greased with cooking spray.
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 bake this in the oven instead of the microwave?
I've done it at 350°F for about 12 minutes in a ramekin. The texture comes out slightly firmer, more like a low carb cookie bar than the soft, gooey center you get from the microwave. Both are good, just different. I still prefer the microwave version because the whole point is speed. If you're already heating up the oven, my keto chocolate cake is worth the extra time.
Why did my mug cake come out rubbery?
Two things cause this: overmixing and overcooking. I just stir until the dry ingredients are incorporated and stop. No need to beat it smooth. And pull it from the microwave when the top looks set but the center still jiggles slightly. It firms up as it cools. The first time I made this, I left it in for a full 90 seconds and it bounced like a rubber ball. Now I start checking at 60 seconds.
What size mug should I use?
I use a 12-ounce mug and it works perfectly. The batter fills it about halfway, which gives it room to rise without overflowing. I've also split it between two smaller mugs (about 8 ounces each) when my kids both want one. Anything under 10 ounces for a single batch and you'll be cleaning your microwave.
Can I make this dairy-free?
I've swapped the butter for coconut oil and it works. The texture stays the same, maybe slightly denser. I haven't tried ghee but I'd expect similar results. The flavor shifts a little (you lose that buttery richness), but with the chips in there you barely notice.
Can I use a different flour instead of almond flour?
Coconut flour works, but you need way less. I use 1 tablespoon of coconut flour instead of the 2 tablespoons of almond flour, and add about a tablespoon of extra liquid (milk or water). Coconut flour is much more absorbent, so if you use the same amount you'll get something dry and crumbly. I tested both side by side and the almond flour version has a better cookie-like chew. If you want to explore almond flour baking further, my almond flour cookies use a similar ratio.
What sweetener works best?
I use monkfruit sweetener because I like the taste and it measures 1:1 with sugar. Erythritol works too but can leave a slight cooling sensation. I've tried stevia drops and they work in a pinch, but sweetness levels vary a lot between brands so start with less and adjust. For a sugar-free dessert this small, the sweetener choice really comes through, so use one you actually like the taste of.
How do I store leftovers?
I keep leftovers in an airtight container in the fridge for up to 2 days. A quick 10-15 seconds in the microwave brings it back. Honestly though, I usually eat the whole thing in one sitting. If I know I'll want another one tomorrow, I just make a fresh batch since it takes two minutes.
Can I add toppings?
I top mine with a spoonful of whipped cream and a few extra chips while it's still warm so they get melty. Chopped pecans or walnuts are good too. If you want a totally different single-serving dessert, my pumpkin version is what I reach for once fall hits.
If you miss cake and chocolate chip cookies on a low carb diet, I’ve got a keto chocolate chip mug cake for you! This easy sugar free mug cake is a vanilla cake base with sugar-free chocolate chips mixed in. It tastes like you are eating a cookie cake.
The best part – it’s very easy to make and you can bake up a single serve cake in less than two minutes! All of the ingredients for this portion controlled cake are added to a mug or ramekin and baked in the microwave so you can be enjoying your chocolate chip cake in no time!
The chocolate chips used in this mug cake are sugar-free. There are many companies coming out with sugar-free chocolate chips and you can often find them in the baking section at the grocery store, especially if you have a Whole Foods or natural grocery store.
My favorite brand of sugar-free chocolate chips is 
I prefer a 
Most mug cakes are baked in the microwave because it’s easier and you can bake your cake quickly. But if you don’t have a microwave or don’t like to use them, you can still make mug cakes in the oven! Bake them in an oven-safe dish, like a 
Mug cake recipes are popular in the keto community because they’re an easy dessert you can make when you have a sweet tooth craving. Here are some of my favorites:
My son grabbed the mug before it even cooled down and burned his fingers trying to scoop it out. That reaction told me more than any taste test could. The two-flour combo is what gets it right, that chewy center instead of the rubbery texture I'd accepted from every other mug cake I'd made. Four times this week. He's stopped asking for regular cake after dinner.
Burned fingers are basically the best review I've ever gotten for this. Four times in a week and he's already moved on from regular cake. That two-flour combo took me forever to get right, so I'm glad it's doing what it's supposed to.
Been keto almost a year and gave up on dessert a while back, figured the substitutes were never worth it. Made this on a quiet Tuesday night when the craving hit hard, and I genuinely teared up a little. That chewy center from the two flours is the thing I thought I'd just never get back.
Stirred a tablespoon of peanut butter in with the melted butter and the center came out so much richer. The two-flour combo is already great for texture, but the peanut butter version is a different thing entirely (in a good way). One note: mine needed the full 85 seconds to set instead of 60, so give it the extra time if you try it.
Never tried mixing it into the butter but I'm doing that tomorrow. And yeah, 85 seconds makes sense with the extra fat slowing the set.
My 8-year-old has been asking for chocolate chip cookies literally every day this week and I needed something fast that wouldn't wreck my macros. Made this in like 3 minutes and she ate the whole thing (I had to make a second one for myself). She said it tastes exactly like a cookie and honestly she's not wrong, the texture is spot-on. We're doing this every time she gets that look on her face now.
8 year olds don't lie about texture. If she said cookie you nailed it. I make these when my boys want something sweet but I need it done before they change their minds.
I just made this chocolate chip mug cake and it's delicious! Will definitely make this one again. Thank you for posting it!
Extra chips on top right when it comes out is how I eat mine. They're melted before you even sit down.
Amazing....
The two-flour combo took me forever to get right. Worth it though.