Name: Microwave Peanut Butter & Banana Mug Cake
Prep time: 5 min
Cook time: 1 min
Total time: 6 min
Ingredients: 1/2 medium banana (mashed); 1 tablespoon peanut butter (or any other nut butter); 1 egg white; 1/4 teaspoon vanilla extract; 4 ½ tablespoons oat flour (30g/1oz); 1/4 teaspoon cinnamon; 1/4 teaspoon baking powder; pinch of salt

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This Microwave Peanut Butter & Banana Mug Cake is your ultimate quick-fix dessert, blending creamy peanut butter and sweet banana in just 6 minutes. The soft, fluffy texture melts in your mouth, while the rich, nutty flavor is perfectly balanced by the natural sweetness of ripe bananas. It’s a warm, comforting treat that feels indulgent yet effortless to make.

Perfect for those moments when you need a little pick-me-up, this mug cake is ready in a flash—no oven required. The gooey center and tender crumb create a delightful contrast, making every bite a mini celebration. Whether it’s a late-night craving or a midday snack, this recipe is your go-to for instant satisfaction.

What You’ll Need

1/2 medium banana, mashed (ripe bananas work best for sweetness)
1 tablespoon peanut butter (or any nut butter like almond or cashew butter)
1 egg white (helps with structure and fluffiness)
1/4 teaspoon vanilla extract (adds a hint of flavor)
4 ½ tablespoons (30g/1oz) oat flour (or grind rolled oats into flour for a DIY option)
1/4 teaspoon cinnamon (optional, but adds warmth)
1/4 teaspoon baking powder (essential for rising)
Pinch of salt (balances the sweetness)

How to Make It

In a large microwavable mug, mash the banana with a fork until smooth.
Add the peanut butter, egg white, and vanilla extract to the mug. Mix well until fully combined.
Gently stir in the oat flour, cinnamon, baking powder, and salt until the batter is smooth and no dry spots remain.
Microwave on high for 45 seconds to 1 minute (timing may vary based on your microwave’s wattage). The cake is done when it’s firm in the middle and springs back lightly when touched.
Top with sliced banana or a drizzle of peanut butter if desired. Enjoy warm!

Toppings and Serving Ideas

Take your mug cake to the next level with fun toppings! Try a drizzle of honey or maple syrup for extra sweetness, or sprinkle on some chopped nuts for crunch. A dollop of Greek yogurt or a scoop of vanilla ice cream makes it feel like a decadent dessert. For a fruity twist, add fresh berries or a handful of chocolate chips.

Recipe Variations to Try

This recipe is super versatile! Swap the peanut butter for almond or cashew butter if you prefer. If you’re out of oat flour, use all-purpose flour or almond flour instead. For a vegan version, replace the egg white with 1 tablespoon of flaxseed meal mixed with 2.5 tablespoons of water. Experiment and make it your own!

Storage and Reheating Tips

This mug cake is best enjoyed fresh, but if you have leftovers, let it cool completely and store it in an airtight container in the fridge for up to 1 day. To reheat, microwave for 15-20 seconds until warm. Note: the texture might be slightly denser after refrigeration.

Microwave Power and Timing Tips

Microwave wattages vary, so keep an eye on your cake as it cooks. Start with 45 seconds and check for firmness in the center. If it’s still gooey, add 10-15 seconds at a time. Overcooking can make it dry, so err on the side of caution. If your microwave is lower than 1200W, you may need an extra 15-30 seconds.

Why This Recipe Works

This mug cake is a quick, healthy treat that’s perfect for satisfying cravings. The banana adds natural sweetness and moisture, while the peanut butter gives it a rich, nutty flavor. Oat flour keeps it gluten-free (if using certified GF oats), and the egg white helps it rise beautifully. It’s a guilt-free indulgence in just minutes!