Name: Microwave Coffee and Walnut Cake
Prep time: 5 min
Cook time: 3 min
Total time: 5 min
Yield: 4
Ingredients: 4 tbsp unsalted butter, softened; 4 tbsp sugar; 1 egg; 4 tbsp self-rising flour; 1 tsp instant coffee, dissolved in 1 tbsp hot water; 2 tbsp chopped walnuts; For the Frosting:; 2 tbsp butter, softened; 4 tbsp powdered sugar; 1 tsp instant coffee, dissolved in 1 tsp hot water; Extra chopped walnuts for topping; Equipment:; A microwave-safe dish (around 6 inches wide); A fork or small whisk for mixing; A microwave

Microwave Coffee and Walnut Cake

The rich aroma of coffee paired with the nutty crunch of walnuts makes for a classic combination that’s hard to resist. In my household, this cake is a go-to when we need something sweet but don’t have the time (or patience) to deal with the oven. Enter the microwave coffee and walnut cake—a game-changer!

I first made this when my kids came home from school craving something sweet, but I was knee-deep in a never-ending to-do list. The idea of whipping up a full cake felt impossible, but then I remembered my trusty microwave. In under 10 minutes, we had a warm, fluffy coffee and walnut cake, complete with a luscious frosting. The best part? It tasted just as indulgent as a traditional oven-baked version!

My husband, a self-proclaimed coffee connoisseur, was skeptical at first. But after one bite, he was hooked. “This tastes like a café-style cake!” he declared, and I knew we had a winner. Now, it’s a staple in our home—perfect for last-minute guests, quick after-school treats, or those nights when I just need something sweet to go with my evening tea.

This recipe is proof that great things don’t always take hours. If you love coffee and walnut cake but want a faster way to enjoy it, this microwave version will be your new best friend.

Questions I Often Get Asked About This Recipe

Can I use instant coffee instead of brewed coffee?
Yes! Instant coffee works great in this recipe. Just dissolve a teaspoon of instant coffee in a tablespoon of hot water before adding it to the batter.

What’s the best type of walnuts to use?
I prefer using chopped walnuts for texture, but you can also finely grind them for a smoother cake consistency. Toasting them beforehand adds extra depth of flavor!

Can I make this cake dairy-free?
Absolutely! Swap out the butter for a dairy-free alternative and use almond or oat milk in the frosting.

How do I store leftovers?
If you happen to have any left, store the cake in an airtight container at room temperature for up to two days or refrigerate for longer freshness.

Can I make this in a mug instead of a dish?
Yes! If you just want a single serving, you can make this as a mug cake by reducing the ingredients proportionally and microwaving for about 1.5 minutes.

What You Need to Make Microwave Coffee and Walnut Cake

Ingredients:

4 tbsp unsalted butter, softened

4 tbsp sugar

1 egg

4 tbsp self-rising flour

1 tsp instant coffee, dissolved in 1 tbsp hot water

2 tbsp chopped walnuts

For the Frosting:

2 tbsp butter, softened

4 tbsp powdered sugar

1 tsp instant coffee, dissolved in 1 tsp hot water

Extra chopped walnuts for topping

Equipment:

A microwave-safe dish (around 6 inches wide)

A fork or small whisk for mixing

A microwave

How to Make Microwave Coffee and Walnut Cake

Mix the Batter: In a microwave-safe dish, cream the butter and sugar together until fluffy. Add the egg and mix well. Stir in the flour, dissolved coffee, and walnuts until smooth.

Microwave the Cake: Microwave on high for 2-3 minutes, or until the cake is firm to the touch. Cooking time may vary depending on your microwave’s power.

Make the Frosting: While the cake cools, mix the butter, powdered sugar, and dissolved coffee together until smooth.

Assemble: Spread the frosting over the cooled cake and sprinkle extra walnuts on top.

Enjoy! Slice and serve with your favorite cup of coffee or tea.

Tips for Making the Best Microwave Coffee and Walnut Cake

Don’t over-microwave – Cooking too long can make the cake dry. Start with 2 minutes and add more time in 10-second increments if needed.

Use room-temperature ingredients – This helps everything mix more smoothly.

Let the cake cool before frosting – Otherwise, the frosting will melt into the cake instead of spreading nicely.

Double the batch – If you want a larger cake, double the ingredients and microwave in a slightly bigger dish.

Reader Reviews

⭐⭐⭐⭐⭐ “This was so easy to make and tasted amazing! Perfect for when I’m craving something sweet but don’t have much time.” – Sarah J.

⭐⭐⭐⭐ “Great texture and flavor. I added a little cinnamon for an extra twist, and it was delicious!” – James P.

⭐⭐⭐⭐⭐ “I love how quick this recipe is! My kids devoured it in minutes.” – Emily T.

⭐⭐⭐ “Tasted great, but I think next time I’ll add more coffee for a stronger flavor.” – Rachel L.

⭐⭐⭐⭐⭐ “Perfect for a last-minute dessert! Will definitely make this again.” – Linda W.

Printable Recipe

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