Some nights I want something chocolate, I want it now, and I’m not turning on the oven for one dessert. This fudgy chocolate mug cake without eggs is what I make.

Flour, sugar, cocoa, and whatever is left in the coffee pot from this morning, stirred together in the mug with a fork, are my kind of heaven. It comes out gooey in the middle with melted chocolate chips across the top.

This recipe has no egg in it. That’s not a diet thing. It’s why this cake stays fudgy instead of turning into a little rubber sponge, which is what happens to so many mug cakes.

A white bowl filled with chocolate mug cake topped with melted chocolate chips sits on a wooden surface.

This mug cake has quickly become one of my go-to desserts alongside other easy single-serve treats like my Strawberry Mug Cake and Nutella Mug Cake. I get a gooey, chocolate dessert while I watch TV with no mess in my kitchen to clean later.

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How to Make This Chocolate Mug Cake

In a mug or ramekin that holds at least 10 ounces, add the flour, sugar, cocoa powder, baking powder, and salt directly into the mug. Use a fork to stir everything together until the dry ingredients are evenly mixed and no cocoa powder lumps remain. Cocoa clumps, and every lump you leave now is a dry, bitter pocket in the finished cake.

A white bowl containing cocoa powder and baking powder on a wooden surface.

Pour in the milk, vegetable oil, and brewed coffee, then mix until the batter looks like thick chocolate paste. Get the fork into the bottom corners of the mug to ensure no dry spots remain.

A hand holds a measuring spoon filled with olive oil above a white bowl containing a gray powder mixture on a wooden surface.

Stir in one tablespoon of chocolate chips until they’re evenly spread through the batter. Sprinkle the remaining tablespoon of chocolate chips right over the top so they melt into the surface as it cooks.

A white bowl filled with dark chocolate batter topped with scattered chocolate chips, placed on a wooden surface.

Microwave on high for 70 to 80 seconds. This will vary, depending on your microwave wattage. Mine is 800 watts, so if yours is higher, cook a little less, and if it’s lower, cook a little longer.

You want to watch for the edges to look set and dry. The center should still look slightly soft and a little shiny for the perfect fudgy texture.

Let the mug cake cool for 2 to 3 minutes before eating, as it continues to cook as it cools. This rest time also helps prevent burns since the melted chocolate chips stay very hot right out of the microwave.

A fork holding a portion of chocolate mug cake with chocolate chips, above a ceramic mug on a wooden surface.

What If I Don’t Have Coffee?

I usually use whatever is left in the coffee pot after the morning, but not everyone drinks coffee regularly. If you don’t have brewed coffee on hand, you can swap in an equal amount of water and a splash of vanilla extract, and it still turns out great.

The coffee helps bring out a richer, deeper, and more chocolatey flavor in the cake, but it doesn’t make the cake taste like coffee. It just makes the chocolate stand out more and taste more intense in every bite.

Why Isn’t There Butter in This Mug Cake?

I don’t use butter in this mug cake because I want the texture to stay as moist as possible. Oil is liquid at room temperature, and butter is not.

In a cake this small, that matters more than usual. Butter firms back up as the cake cools, and the cake tightens along with it, which is the opposite of what I want from something I’m eating out of a mug with a spoon.

Oil keeps it soft and moist. You can use melted butter if that is what you have, but it will not be as fudgy, and it’s not my preference.

Why Doesn’t This Cake Use Eggs?

A whole egg is far too much for a single serving of cake, and there’s no simple way to use a third of one. Add the whole thing, and you get a rubbery, spongy texture instead of a soft fudgy bite.

A chocolate mug cake with melted chocolate chips on top, served in a white ramekin on a wooden countertop.

This eggless chocolate version relies on a bit of oil to keep it rich, tender, and incredibly moist. That simple choice helps the mug cake stay gooey and soft, which is exactly what makes it taste so decadent.

What Size Mug Do I Need?

At least 10 ounces, and wider is better than taller. This is why I love using ramekins for my mug cakes.

The batter climbs while it cooks and settles back down, and a narrow mug either overflows or gives you a dense middle that never quite cooks. If you have a wide mug or teacup, use it.

Troubleshooting

Your cake is still raw in the middle: Add 10 seconds at a time, and check between each one. Don’t add 30 and hope, because you’re likely to overcook it with that strategy.
It’s rubbery or tough: It cooked too long, or the batter got overmixed. Both are fixable next time, and both are easier to overdo than you think.
The mug cake is dry: This is almost always because you added too much flour from scooping it out of the bag. Stir the flour to fluff it, then gently scoop it. Check the measuring before you blame the microwave.
Your cake overflowed: The mug was too small. Use a bigger one next time.