Oat Mug Cake (Healthy 2-Minute Microwave Cake)

An oat mug cake is the healthiest way to get warm cake in two minutes. Oat or whole wheat flour, a spoonful of oat cereal, a little sweetener, an egg and a splash of milk are stirred together in a mug and microwaved until set. The egg makes it rise and gives it a soft, almost soufflé-like texture, and because there is no refined flour or butter, it works as a quick breakfast as well as a snack. For more single-serving treats, try our 100-calorie mug cake or the high-protein Kodiak mug cake.

Why you'll love this

• Ready in about 2 minutes. Mix, microwave and eat.
• Wholesome ingredients. Oat flour, oats, egg and milk.
• No butter or oil. The egg gives it a light, moist texture.
• Breakfast or dessert. Top it with fruit and yogurt or chocolate chips.
• Single serving. No leftovers, no temptation.
• Easy to adapt. Make it with honey, maple syrup or sugar.

Key ingredients & how to use them

• Oat flour or whole wheat flour — one and a half tablespoons. Make oat flour by blitzing rolled oats in a blender until fine.
• Oat cereal — one tablespoon of rolled or quick oats, or oat-based cereal, for texture.
• Sweetener — one tablespoon of sugar, honey or maple syrup. Liquid sweeteners make it slightly moister.
• Milk — two tablespoons of dairy or plant milk.
• Egg — one. It is the main structure and lift in this mug cake; use a vegan egg substitute if needed, though the texture will be denser.

How to make it (step by step)

1. 1

   Choose the right mug

   Use a clean, microwave-safe mug that holds at least 8 oz (240 ml). The batter rises as it cooks, and a small mug will overflow.

2. 2

   Mix the dry ingredients

   Add the oat or whole wheat flour, oat cereal and sweetener to the mug and stir with a fork so there are no lumps. If you are using honey or maple syrup, add it with the wet ingredients instead.

3. 3

   Add the milk and egg

   Add the milk and the egg and beat with the fork until completely smooth, scraping the bottom and corners of the mug so no dry flour is hiding there.

4. 4

   Microwave

   Cook on high for 1 minute 30 seconds. If the centre still looks wet, add 15 to 30 seconds. Microwaves vary, so check early the first time you make it.

5. 5

   Rest and top

   Let the mug cake sit for 1 to 2 minutes — it keeps cooking and is extremely hot. Eat it as it is, or add fruit, yogurt or a few chocolate chips.

Troubleshooting

• It is rubbery. It was overcooked. Microwave in shorter bursts and stop when the top is just set.
• It tastes eggy. Add a pinch of cinnamon and a drop of vanilla, and make sure the batter is fully mixed.
• It overflowed. The mug was too small. Use one that holds at least 8 oz.
• The centre is raw. Cook for another 15 seconds and check again.
• Dry pockets of flour. Scrape the bottom of the mug well when mixing.
• It sank. It is normal for a mug cake to deflate a little as it cools.

Is an oat mug cake healthy?

Compared with a classic mug cake made with white flour, sugar and oil, this oat mug cake is lighter and more nourishing. The oat flour and oats bring fibre and keep you full for longer, the egg adds protein, and there is no added fat. You control the sweetness, so you can use as little as a teaspoon of honey or maple syrup, or a zero-calorie sweetener.

It is still a treat if you load it with chocolate, but topped with fruit and yogurt it makes a quick, warm breakfast. If you want even more protein, our protein powder mug cake is built for post-workout snacking.

Serving ideas

Serve the oat mug cake warm with Greek yogurt and berries for breakfast, or with a few chocolate chips and a spoonful of peanut butter as a snack. For a treat-day version, try our Biscoff mug cake.