This microwave brownie in a mug is a quick, easy, and satisfying dessert that can be made in less than 15 minutes with simple ingredients and a microwave-safe mug!
With their gooey texture, chocolatey flavor, and simple preparation, brownie mug cakes have become a popular treat for those with a sweet tooth who don’t want to spend too much time or effort in the kitchen. I’ve done all the testing for you to achieve everything you love about a brownie in one little single-serve brownie mug cake.
Top your fudgy brownie with whipped cream and this Microwave Hot Fudge Sauce for added decadence!
If you’re a fan of similar small-batch desserts, be sure to try Molten Lava Cake, Mini Chocolate Cream Pie in Mason Jars, and Nutella Cupcakes. And if you can’t even wait 1 minute to eat your brownie, skip the microwave and dig into a bowl of edible brownie batter!
What do I Need for this Recipe?
- All-purpose flour – Use gluten-free flour like Bob’s Red Mill for gluten sensitivities.
- Cocoa powder – I prefer Dutch-process cocoa powder, but you can use another type or whatever you have on hand. This easy mug brownie recipe is sweet enough which is why I prefer unsweetened cocoa powder.
- Granulated sugar – you can substitute brown sugar here.
- Salt – Just a pinch of salt.
- Pure vanilla extract – Almond extract can be added too. When using this recipe for Christmas, consider adding peppermint extract to the batter.
- Milk – Whole milk or reduced-fat milk.
- Vegetable oil – Coconut oil (unscented) or canola oil can be used.
- Chocolate chunks or chips – White chocolate chips, semi-sweet chocolate chips, or dark chocolate chips. You can also use alternatives such as peanut butter chips or butterscotch chips.
- Egg – Beaten. This can be omitted, but I recommend including it in the batter. It gives a little rise to the brownie and the texture is much better with the egg. You are using just one tablespoon of a beaten egg – you can make about three brownie mug cakes from one egg.
I sprinkled half of the chocolate chips/chunks over the top of the mug brownie before heating it in the microwave. You could also garnish the cooked brownie with whipped cream, sprinkles, chopped nuts, chopped candy canes (for a holiday version), or a drizzle of chocolate syrup.
A 6-8 oz microwave-safe size mug, separate bowl, small whisk, or fork.
Variations and Substitutions:
- Any kind of chocolate chip or chocolate chip alternative (i.e., peanut butter chips or butterscotch chips) can be used.
- Add chopped nuts to this brownie mixture for added texture.
- For a holiday brownie in a mug, add peppermint extract to the brownie batter. Almond extract is another great flavor option.
- Make a gluten-free brownie in a mug using gluten-free flour such as Bob’s Red Mill or almond flour.
- Add some espresso powder to this chocolate brownie to make a coffee mug brownie instead!
- Omit the egg and use coconut milk or almond milk for a vegan mug brownie.
Step 1: Stir together the dry ingredients in a 6-8 oz. microwave-safe mug.
Step 2: Add vanilla, milk, and vegetable oil to the mug and stir to make a batter.
Step 3:In a separate bowl, use a fork or small whisk to thoroughly beat one egg. Measure out 1 tablespoon of the beaten egg and add it to the mug.
Step 4: Mix in ½ of the chocolate chunks.
Pro Tip: Ensure that you choose a microwave-safe mug for this recipe. There’s usually an icon or wording underneath a mug that will tell you whether it’s suitable for microwaving. It’s also recommended to use a 6-8oz mug for this recipe.
Step 5: Sprinkle the other half over the top. Microwave 1 minute – 1 minute 15 seconds.
Step 6: The mug cake is done when it no longer appears wet across the top.
GARNISH/SLICE/SERVE: You can dig right in or top the brownie with a scoop of ice cream or a squirt of whipped cream. Add caramel or chocolate sauce – you can even add sprinkles!
- The brownie made in a mug won’t rise much, just a little, so it’s best to use a 6-8 oz mug. The brownie may not fill the mug to the top edge due to variations in the shape and size of the mug, but it will still taste delicious.
- Mix the dry ingredients together first to ensure they’re well combined, then add the wet ingredients.
- Adding one tablespoon of egg to the recipe adds some leavening and results in a chewier brownie. Even a small amount of egg can make a difference in the taste and texture of your brownie in a mug. However, if you prefer to skip this ingredient, the brownie will still turn out great.
- One egg makes about three recipes of brownies in a mug.
- Store the remaining beaten egg in an airtight container in the fridge for up to 1-2 days to use in other recipes or as an egg wash for pastries. Don’t store it for longer than this, as it’s susceptible to bacteria growth.
- Enjoy this microwave brownie as is or alongside a scoop of vanilla ice cream.
- I don’t recommend that you use a brownie box mix for this single-serving brownie recipe. I have tested all the variations of ingredients to get the perfect combination of flavor, texture, and the ability to cook it in the microwave.
- If you omit the egg in this easy recipe, it may be worth adding a small amount of baking powder for rise.
The brownie-in-a-mug recipe originated in the early 2000s, around the same time that microwave cooking was becoming increasingly popular. The first known recipe for a brownie in a mug was published in a book called “101 Things to Do with a Cake Mix” by Stephanie Ashcraft in 2002.
Since then, the recipe has become incredibly popular, with countless variations. Some people even refer to it as a “mug cake” or a “microwave cake” and use different flavors and toppings to create a wide variety of desserts.
Yes! You can store your sweet treat at room temperature for up to 3 days, covered tightly with plastic wrap.
Dutch process cocoa powder, also known as Dutch-processed cocoa or alkalized cocoa, is a type of cocoa powder that has been treated with an alkaline solution to reduce its acidity. This process involves washing cocoa beans in a potassium solution, which neutralizes their natural acidity and produces a darker, smoother fudgy mug brownie.
While it’s possible, I don’t recommend it. From testing this single-serve brownie recipe, I’ve found that increasing the amounts in the recipe without adjusting the recipe itself and the cooking time can lead to undercooked or burnt brownies. If you’d like two mug cakes (to share or both for yourself!), simply mix up two separate brownies in a mug.
Microwave Brownie in a Mug
- 3 tablespoons all-purpose flour
- 3 tablespoons dutch-process cocoa powder
- 3 tablespoon granulated sugar
- Pinch of salt
- ¼ teaspoon vanilla extract
- 3 tablespoon milk
- 3 tablespoon vegetable oil
- 2 tablespoons chocolate chunks or chips
- 1 tablespoon beaten egg see notes
- Stir together the dry ingredients in a 6-8 oz. microwave-safe mug.
- Add vanilla, milk, vegetable oil to the mug and stir to make a batter.
- In a separate bowl, use a fork or small whisk to thoroughly beat one egg. Measure out 1 tablespoon of the beaten egg and add it into the mug.
- Mix in ½ of the chocolate chunks and sprinkle the other half over the top.
- Microwave 1 minute – 1 minute 15 seconds. The mug cake is done when it no longer appears wet across the top of the mug cake.