Keto Tiramisu Mug Cake

Tiramisu is one of those desserts that feels fancy, but this keto mug cake version keeps things simple. You only need a mug, a microwave, and a few minutes.

I wanted to recreate that combination of coffee-soaked cake and smooth mascarpone cream in a way that’s completely low carb and keto friendly. And honestly, it turned out better than I expected.

The cake itself is soft and spongy, made with almond flour and coconut flour. Once you soak it with the espresso mixture, it gets that moist, almost custardy texture that real tiramisu is known for.

Then you top it with a quick mascarpone cream and a dusting of cocoa powder. It looks and tastes like something from a restaurant, but it takes just a few minutes to put together.

This is a single-serving recipe, so there’s no leftover temptation either. Just one perfectly portioned keto dessert whenever you’re in the mood.

Why You’ll Love This Recipe

Ready in Under 5 Minutes – This keto tiramisu mug cake goes from mixing to eating in about 5 minutes flat.

Tastes Like Real Tiramisu – The espresso soak and mascarpone cream give you that authentic tiramisu flavor without any sugar.

Soft and Spongy Texture – The cake comes out light and airy instead of dense like most low carb mug cakes.

Recipe Ingredients

For the Espresso Soak

• 2 tbsp Hot Brewed Espresso or Strong Coffee
• 1 tsp Granulated Erythritol

For the Cake

• 3 tbsp Almond Flour
• 1 tbsp Coconut Flour
• 2 tbsp Granulated Erythritol
• 1/2 tsp Baking Powder
• 1 Large Egg
• 2 tbsp Melted Butter
• 1 tbsp Heavy Cream
• 1/2 tsp Vanilla Extract
• Pinch of Salt

For the Mascarpone Cream

• 2 tbsp Mascarpone Cheese
• 1 tbsp Heavy Cream
• 1 tbsp Powdered Erythritol
• 1/4 tsp Vanilla Extract
• Unsweetened Cocoa Powder, for dusting

How To Make

Step 1

Stir together the hot espresso and erythritol until dissolved. Set aside to cool slightly while you prepare the rest.

Step 2

In a microwave-safe mug (at least 12 oz), whisk together the almond flour, coconut flour, granulated erythritol, baking powder, and salt.

Step 3

Add the egg, melted butter, heavy cream, and vanilla extract. Stir until the batter is completely smooth.

Step 4

Microwave on high for 60 to 70 seconds, until the cake is just set on top. It should be soft and spongy, not dense or overcooked.

Step 5

Immediately poke several holes across the top of the hot cake using a toothpick or fork. Slowly drizzle the espresso mixture over the surface, letting it soak down into the holes and saturate the cake. Let it absorb for 1 to 2 minutes.

Step 6

While the coffee soaks in, whisk together the mascarpone cheese, heavy cream, powdered erythritol, and vanilla extract until smooth and thick but spreadable.

Step 7

Spoon the mascarpone cream over the soaked cake, spreading it to the edges. Dust the top generously with cocoa powder through a small sieve for that classic tiramisu finish. Serve immediately or refrigerate for 20 minutes if you prefer it chilled.

Tips

Let the Espresso Cool Slightly Before Soaking

You don’t want to pour boiling hot espresso over the cake. If it’s too hot, it can partially dissolve the top layer and turn it mushy instead of giving you that nice moist soak.

Let it cool for about 2-3 minutes after you dissolve the erythritol. It should still be warm but not steaming. Warm espresso absorbs into the cake better than cold espresso, so don’t let it cool completely either.

Don’t Overcook the Cake

Start checking the cake at 60 seconds. You want it to look just barely set on top, maybe even slightly wet in the center. It will continue cooking for a few seconds after you take it out.

If you microwave it until it looks fully done, it’ll end up rubbery and dry. That’s the most common mistake with mug cakes.

Every microwave is different, so if yours runs hot, try 50 seconds first and add time in 10-second bursts. A slightly underdone mug cake is always better than an overdone one, especially since the espresso soak adds moisture back in.

Poke Deep Holes for the Espresso Soak

When you poke holes in the cake, don’t just scratch the surface. Push the toothpick or fork all the way down to the bottom of the mug so the espresso can travel through the entire cake.

Make at least 15-20 holes spread evenly across the surface. The more holes you make, the more evenly the coffee flavor will distribute instead of just sitting on top.

Drizzle the espresso slowly in small amounts, letting each bit absorb before adding more. If you pour it all at once, it’ll pool on top and make the surface soggy while the bottom stays dry.

More Recipes

• Keto 90-Second Chocolate Mug Cake
• Keto Funfetti Mug Cake
• Keto Tiramisu Brownie Bars
• Low Carb Tiramisu Cups
• Keto Mocha Panna Cotta

Frequently Asked Questions

Can I use instant coffee instead of brewed espresso?

Yes, you can dissolve 1 to 2 teaspoons of instant coffee granules in 2 tablespoons of hot water and use that as your espresso soak. It works just as well and is actually more convenient if you don’t have an espresso machine at home.

Just make sure it’s fully dissolved before you drizzle it over the cake so the flavor distributes evenly throughout.