This keto brownie in a mug is gooey and decadent, and serves just one person. It’s the perfect single-serve dessert when you need chocolatey goodness but you don’t want the leftovers.
Add a scoop of keto ice cream for the ultimate indulgence.
Don’t say I never do anything nice for you. Because not only do I give you the recipe for this delicious keto mug brownie, but I also provide you with three different ways to bake it!
I show you how to bake this same recipe in an oven, in an air fryer, and in a microwave. So no matter what equipment you’ve got on hand, you can enjoy a delicious keto dessert.
How’s that for a full service keto food blog?
Single Serve Keto Brownie
Usually when I make keto brownies, it’s the “whole pan to feed a crowd” type of recipe. My family can put a pretty good dent in a pan of brownies before you can bat an eye.
But sometimes I need a treat that is just mine, and mine alone.
I developed this keto mug brownie almost 6 years ago now, but I decided it needed an update. My goal was to reduce the carbs but make it just as gooey and rich as it always was.
I also experimented with the cooking method, to see if I could get the same results in an air fryer and a microwave.
And it worked perfectly every way I tried it. Now we all have more options and you can’t beat that!
This keto brownie takes basic low carb ingredients that you can find in almost any grocery store. You will need:
- Keto sweetener: I recommend using a powdered sweetener like Swerve Confectioners so it blends in better.
- Egg: You just need two teaspoons and carton eggs or egg whites work well.
- Vanilla extract
- Almond flour: Use finely ground, blanched almond flour for best results.
- Cocoa powder
- Baking powder
- Water or cold coffee
- Chopped nuts or sugar-free chocolate chips (optional)
How to make keto brownie in a mug
This recipe is ridiculously easy to make, and you have three different ways to bake it. Here are my best tips for getting it right:
The brownie batter
- Melt the butter: Use a microwave safe bowl and cook on high until just melted but not too hot.
- Whisk in the sweetener: I recommend a powdered sweetener so that it dissolves well.
- Add the egg and vanilla: You need such a small amount of egg but it’s important to measure it out carefully. You can whisk a whole egg, or use eggs from a carton.
- Stir in the dry ingredients: Make sure everything is well combined and break up any clumps in the almond flour and cocoa powder.
- Add a little liquid: At this point, the batter will be quite thick. Add 1 tablespoon of water or cold coffee to thin it out.
- Sprinkle with some toppings: I really like some finely chopped pecans, for crunch. But a few keto-friendly chocolate chips work too.
You can use a regular oven or a smaller countertop oven. Bake it at 325ºF for 10 to 15 minutes – the less you bake it, the more gooey it will be.
Air fryer method
This may be my favorite method, as I think it produced the best results. It was like a cross between a brownie and a chocolate lava cake!
Bake it at 325ºF for 7 to 9 minutes. Again, the less you bake it, the gooier it will be.
In a hurry to enjoy this keto mug brownie? You can cook it in less than 1 minute in your microwave! It does end up a little more spongy, as microwave cakes usually do. But it’s still delicious.
I found that starting and stopping the microwave in 15 second increments helped keep the brownie from spilling over the ramekin. Check on it frequently so you know when it’s the right consistency for you.
Frequently Asked Questions
Coconut flour won’t work in this recipe but you can use sunflower seed flour. It is a 1:1 replacement with almond flour.
Absolutely! Use coconut oil or another dairy-free alternative to butter. If it’s a liquid oil like avocado, there is no need to melt it first.
Yes but do keep in mind that sweeteners such as allulose can affect the consistency. I find that baked goods end up more puffy and cake-like when I use allulose as the main sweetener.
Absolutely! Just double or triple the recipe and divide the batter among more ramekins. Cook as desired.
Keto Mug Brownie Recipe
- In a small microwave safe bowl, melt the butter in the microwave. Stir in the powdered sweetener until well combined, then stir in the egg and vanilla extract.
- Add the almond flour, cocoa powder and baking powder, then add water and stir until the mixture is smooth.
- Transfer the batter to a small (4-ounce) ramekin and sprinkle with chopped nuts, if desired.
To bake in the oven (or toaster oven)
- Preheat the oven to 325ºF and bake the brownie 10 to 15 minutes, depending on how gooey you want it to be.
To bake in an air fryer
- Preheat the air fryer to 325ºF and bake the brownie 7 to 9 minutes, depending on how gooey you want it to be.
To bake in a microwave
- Microwave on high in 15 to 30 second increments, stopping the microwave in between so that it doesn't spill over. A total of 45 to 60 seconds should be enough.