Craving something sweet but don’t want to make an entire cake? This Vanilla Blueberry Keto Cake in a Mug is the perfect little treat.
Made with coconut flour, full-fat cream cheese, butter, vanilla, and fresh blueberries, this single-serving cake comes together in just minutes. Everything is mixed directly in a microwave-safe mug, so there’s very little cleanup afterward.
The result is a soft, tender cake with a buttery vanilla flavor and little bursts of juicy blueberries throughout. It’s a convenient option when you want a quick low-carb-style dessert without preparing a whole batch.
Ingredients
- 1 tablespoon butter
- 2 tablespoons full-fat cream cheese
- 2 tablespoons coconut flour
- 1 tablespoon keto-friendly sweetener
- 1 teaspoon vanilla extract
- 1/4 teaspoon baking powder
- 1 large egg
- About 12 blueberries
Instructions
1. Soften the Butter and Cream Cheese
Add the butter and cream cheese to a microwave-safe mug.
Microwave for about 20 seconds, just until softened. If needed, stir until smooth.
Avoid overheating the mixture, as you don’t want it to become extremely hot before adding the egg.
2. Make the Cake Batter
Add the coconut flour, sweetener, vanilla extract, baking powder, and egg directly to the mug.
Stir thoroughly until the mixture is smooth and the ingredients are evenly incorporated.
Use a spoon or small spatula to scrape down the sides of the mug.
3. Add the Blueberries
Gently fold the blueberries into the batter.
Try not to crush them too much. Keeping some of the berries whole gives you delicious bursts of blueberry flavor as you eat the cake.
4. Microwave
Place the mug in the microwave and cook for approximately 1 minute.
Check the center. If it still looks wet or undercooked, microwave it in short 5–10 second intervals until set.
Microwave cooking times vary considerably depending on the wattage of your microwave and the size and shape of your mug, so avoid automatically adding extra cooking time.
5. Cool Before Serving
Allow the mug cake to cool for about 5 minutes before eating.
The cake will continue to firm up slightly as it cools.
Enjoy it directly from the mug or carefully transfer it to a small plate.
Tips for the Best Keto Mug Cake
Use a wide mug: A wider, microwave-safe mug helps the cake cook more evenly than a very narrow or tall mug.
Don’t overcook it: Overcooking can make coconut-flour cakes dry and rubbery. Start with the shortest cooking time and add a few seconds only when necessary.
Mix thoroughly: Coconut flour absorbs liquid quickly, so make sure there are no dry pockets remaining in the batter.
Use fresh blueberries: Fresh berries work beautifully and provide juicy bursts throughout the cake.
Let it rest: A few minutes of cooling makes a noticeable difference in the texture.
Can I Use Frozen Blueberries?
Yes. Frozen blueberries can be used, although they may release more moisture and slightly change the color of the cake.
Add them while frozen and fold them in gently. You may need a few extra seconds of microwave time depending on how cold the berries are.
Sweetener Options
The sweetener you choose will affect the flavor and texture of the finished cake.
A granulated keto-friendly sweetener such as erythritol or a monk-fruit-based blend can work well. Since different sweeteners have different levels of sweetness, adjust the amount according to the product you’re using.
Optional Toppings
The mug cake is delicious on its own, but you can make it extra special with:
- A few fresh blueberries
- A spoonful of unsweetened whipped cream
- A small dollop of Greek yogurt
- A sprinkle of cinnamon
- A few chopped nuts
- A light drizzle of sugar-free blueberry sauce
Storage
This recipe is best enjoyed fresh because mug cakes can become firmer as they sit.
If you have leftovers, cover the mug or transfer the cake to an airtight container and keep it at room temperature for up to 1 day. For the best texture, gently warm it before serving.
A Quick Note About “Keto”
Whether this cake fits a particular ketogenic or low-carbohydrate eating plan depends on the exact ingredients and portion sizes you use, especially the sweetener, cream cheese, and blueberries.
For strict carbohydrate tracking, check the nutrition information on your specific products and calculate the carbohydrates according to your portion.
Final Thoughts
This Vanilla Blueberry Keto Cake in a Mug is a wonderfully convenient dessert when you want something sweet without making an entire cake.
With just a handful of ingredients and about a minute in the microwave, you can enjoy a warm, buttery vanilla cake filled with juicy blueberries. It’s quick, comforting, and perfect for satisfying a dessert craving in a single serving.