If you love chocolate but want something quick, easy, and a bit healthier, this 5-minute microwave chocolate chip mug cake is a total game changer. It’s perfect for breakfast, a snack, or whenever you need a little chocolate fix without any fuss. With just six simple ingredients — all wholesome and naturally sweetened — it comes together in minutes and tastes like a treat you can feel good about.
No need to heat up the oven or pull out a mixing bowl; just grab a mug, mash your banana, and you’re almost there. The oats add fibre and keep you fuller for longer, while the almond butter adds a subtle nuttiness and a hit of protein. Dark chocolate chips give that rich chocolatey burst, but without overloading on sugar.
I love this recipe because it feels indulgent but is actually nourishing and super satisfying. Plus, it’s a perfect solo portion, so you don’t have leftovers tempting you! Whether you’re rushing out the door or settling down with a cosy cuppa, this mug cake has got you covered.
Step-By-Step Instructions
Step 1 – In a mug, add the banana and mash with a fork. Step 2 – Add the egg, almond butter, baking powder and oats. Mix well. Step 3 – Wipe down the edges with paper roll. Step 4 – Add the chocolate chips and stir them in. 
Step 5 – Microwave it: follow the instructions below!
Choosing the Right Mug
When making a mug cake, the size of the mug really matters. You’ll want to use a large microwave-safe mug (around 445 ml / 15 oz) to give the cake enough space to rise without spilling over the sides. If your mug is too small, the batter may overflow, and if it’s too wide, the cake can cook unevenly and turn out dry. I find a regular tea or coffee mug works perfectly—just make sure it’s deep rather than shallow for the best results. For reference, the one I used was about 9 cm across and 7 cm tall, and it worked perfectly without any mess.
The Trick to a Perfect Mug Cake
Microwaving in short bursts is the secret to a soft, fluffy mug cake. If you cook it all at once, the outside can become rubbery while the centre stays undercooked. By microwaving for 1 minute, then two shorter bursts of 30 seconds, the cake rises evenly and sets perfectly without drying out. It’s a simple trick that guarantees a light, moist result every time.
Microwave (Short-Burst Method)
- Place the filled mug on a microwave-safe plate.
- Microwave for 1 minute on full power, then stop and check.
- Microwave for another 30 seconds, stop again.
- Finish with a final 30 seconds until the cake has risen and the top looks just set.
Oven option: You can also bake the mug cake at 180°C / 350°F (static oven) for 18–20 minutes until set.
Tips
- Mashing the banana: Mash the banana really well to avoid lumps and ensure the cake texture is smooth.
- Microwave power: Microwave times may vary depending on your microwave wattage. Start with 1 minute and add 30-second bursts to avoid overcooking.
- Prevent overflow: Wipe the edges of the mug before microwaving to prevent batter from bubbling over.
- Texture preference: For a softer cake, reduce the oats slightly; for a denser, more filling cake, add a little more oats.
- Serving: Enjoy straight from the mug or tip out onto a plate for a more traditional cake feel.
Swaps
Oats: Ground almond should work too but it will have a different texture and flavour.
Banana: Swap with unsweetened applesauce for a different flavour and texture.
Almond butter: Try peanut butter, cashew butter, or sunflower seed butter for a nut-free option.
Chocolate chips: Use chopped dark chocolate, cacao nibs, or dried fruit pieces like raisins or chopped dates.
Egg: Use 1 tbsp of ground flaxseed mixed with 3 tbsp water (let sit 5 minutes) for a vegan alternative.
Storage
Fridge: Store for up to 3 days in the mug or transferred to a sealed container. Reheat gently in the microwave or enjoy cold—it becomes more pudding-like in texture.
Freezer: Not ideal for freezing once cooked, but you can freeze the blended mix (before cooking) in a small container. Defrost overnight and microwave when ready.
More Healthy Desserts
5-Minutes Mug Cake
Ingredients
- 1 egg
- 30 g ground oats, (I simply blended the rolled oats)
- 1 banana
- 1 tsp almond butter
- ½ tsp baking powder
- chocolate chips, I use dark chocolate
Instructions
- Break down the banana into a mug. Mash and add the almond butter. Mix.
- Add the egg, baking powder and mix well.
- I like to wipe down the edge of the mug with kitchen paper. Add the chocolate chops
- Microwave 1 min, stop. Then 30 secs, stop. And another 30 secs.
Video
Notes
- High in protein from the egg and oats, making it a more balanced sweet treat
- Naturally gluten-free if made with GF oats
- No refined sugar — sweetened naturally with honey
- Microwaving in short bursts helps the cake rise evenly and stay soft and fluffy
- Can also be baked in the oven at 180°C / 350°F (static) for 18–20 minutes for a more traditional sponge texture