100 Calorie Mug Cake (Chocolate, Ready in 5 Minutes)

This 100 calorie mug cake is a small, warm chocolate cake that fits easily into a calorie budget. It uses just a tablespoon of flour, a teaspoon of cocoa, a zero-calorie sweetener and half a teaspoon of oil, and rises with a pinch of baking soda and a splash of vinegar. One minute in the microwave and it is ready. It is a little smaller than a standard mug cake — that is how it stays near 100 calories — but it is moist, chocolatey and satisfying. For a heartier healthy option, try our oat mug cake.

Why you'll love this

• About 100 calories. Portion-controlled by design.
• Ready in 5 minutes. Including mixing.
• Real chocolate flavour. Cocoa and an optional few chocolate chips.
• Microwave or oven. Two methods included.
• Pantry ingredients. Flour, cocoa, oil, vinegar and baking soda.
• No eggs. Baking soda and vinegar make it rise.

Key ingredients & how to use them

• All-purpose flour — one tablespoon. Measure it accurately; a heaped spoon makes the cake dry.
• Zero-calorie granulated sweetener — one tablespoon keeps the calories down. Sugar works but adds about 45 calories.
• Cocoa powder — one teaspoon of unsweetened cocoa for chocolate flavour with very few calories.
• Baking soda and white vinegar — an eighth of a teaspoon of soda and a quarter teaspoon of vinegar react to make the cake rise without an egg.
• Oil — half a teaspoon keeps it moist without many calories.
• Water or milk — one tablespoon. Water keeps the calories lowest; milk makes it richer.
• Chocolate chips — optional, one teaspoon, for melty pockets (adds about 20 calories).

How to make it (step by step)

1. 1

   Pick a mug

   Use a microwave-safe mug that holds at least 8 oz (240 ml). For the oven method, use a small oven-safe ramekin instead.

2. 2

   Mix the dry ingredients

   Add the flour, sweetener, cocoa powder, salt and baking soda and stir with a fork until there are no lumps of cocoa.

3. 3

   Add the wet ingredients

   Add the vinegar, oil, vanilla and water or milk and stir until smooth. The vinegar reacts with the baking soda to give the tiny cake its rise, so mix and cook straight away. Fold in the chocolate chips if using.

4. 4

   Microwave

   Cook on high for 60 seconds. If the centre is still wet, add 10-second bursts until the top is just set. It should look slightly moist rather than dry.

5. 5

   Or bake

   For an oven version, bake in a ramekin at 175°C (350°F) for 10 to 12 minutes, until a toothpick comes out with a few moist crumbs.

6. 6

   Cool and enjoy

   Let it cool for 1 to 2 minutes before eating — mug cakes are extremely hot inside.

Troubleshooting

• It is dry. It was overcooked, or the flour was heaped. Level the flour and stop cooking when the top is just set.
• It is rubbery. Too long in the microwave. Cook in 10-second bursts.
• It tastes bitter. Too much baking soda or unmixed lumps. Measure the soda carefully and stir well.
• It did not rise. The batter sat too long before cooking. Microwave straight after mixing.
• It overflowed. Use a bigger mug.
• Sweetener aftertaste. Try an erythritol-monk fruit blend, or a teaspoon of real sugar.

How it stays near 100 calories

Most mug cakes land between 350 and 500 calories because they use four tablespoons of flour, several of sugar and two of oil or butter. This version scales everything down and swaps the heaviest ingredients. A tablespoon of flour is about 28 calories, a teaspoon of cocoa about 4, half a teaspoon of oil about 20, and a zero-calorie sweetener adds none. With water, that comes to roughly 55 to 60 calories; a teaspoon of chocolate chips and using milk bring it close to 100.

The figure is an estimate and depends on your exact ingredients and how generously you measure, but it gives you a warm chocolate dessert for a fraction of the calories of a standard slice of cake.

Serving ideas

Enjoy it on its own, with a few fresh berries, or with a spoonful of light whipped topping. For a protein-packed alternative, try our protein powder mug cake or the paleo chocolate mug cake.