2 Minute Oatmeal Mug Cake (Fluffy, No Flour)

Looking for an easy gluten-free treat to make in minutes? Whip up this fluffy oatmeal cake in a mug with no flour required, only oats! Using my simple hack, stirring halfway through, means a light, fluffy, yet moist, texture every time! Oat mug cakes use simple ingredients, right in your kitchen, so you can enjoy this dessert (or breakfast) right now, in only 2 minutes!

Easy Oat Cake in a Mug

If you are looking for a healthy and affordable gluten-free baking alternative, using oatmeal or homemade oat flour has become a favorite option of mine. Because oats simultaneously build structure and acts as a binder, 100% oat recipes require no flour!

Oatmeal mug cake is no exception. Using only simple ingredients, such oats, milk, egg, maple syrup (or brown sugar), oil, and baking powder, means you can enjoy this treat whenever the fancy strikes. And, like almond flour mug cake, it can easily be modified for dairy-free or sugar-free.

Flourless oatmeal mug cake not only makes a lovely dessert option, but may also be served as a delicious gluten-free breakfast, which kids particularly love. Instead of topping with chocolate chips, whipped cream or ice cream, dollop on a scoop of peanut butter, chopped nuts, or fresh berries.

Below I will show you how to make oatmeal mug cake, along with workable ingredient swaps, tips for preventing a rubbery cake, topping ideas, along with many easy tips to make a perfectly fluffy oat cake in a mug every time!

Ingredient Notes

Mug cake recipes are particularly great for different dietary needs and preferences. Use the suggested substitutions and variations listed below for a gluten-free mug cake, dairy-free, healthy, or even protein-rich.

• Egg – Using one whole egg best mimics the texture of cake. However, for a vegan or egg-free option replace with 1/2 mashed banana. Please note, the texture will be more liked baked oatmeal than cake.
• Oil – Also ideal for a fluffy cake texture, but any preferred oil may be used, such as canola or melted coconut oil. To add protein or a nutty flavor, substitute an equal amount of creamy peanut butter, but this also results in a slightly more dense texture.
• Sweetener – Using pure maple syrup yields the best results. Brown sugar or coconut sugar will also work, but may dry out texture. If making a breakfast mug cake or a healthy dessert, you may also reduce the amount of sweetener. I have not tried this recipe with a sugar-free substitute, but I see no reason why it wouldn’t work as well.
• Oats – Use quick-cooking oats or oat flour for best results. Old fashioned rolled oats may be used, but the crumb will be heavier and more rustic. For a gluten-free mug cake, be sure to use certified gluten-free oats.
• Milk – For a dairy-free recipe, replace with soy, oat milk, almond milk, or any preferred non-dairy substitute.
• Chocolate chips – Optional, but tasty! Using miniature chocolate chips stays more evenly dispersed throughout the batter. They may also be omitted for dairy-free or a healthier alternative.

how to make Oatmeal Mug Cake

(Below shows step-by-step photos and modified instructions. For the complete recipe, along with ingredient amounts, scroll down to the recipe card.)

1. Grease a 10 ounce microwave-safe mug or ramekin with nonstick cooking spray. Use a fork to whisk together the wet ingredients – egg, maple syrup, oil, milk, and vanilla extract.
2. Stir in the dry ingredients – oats, baking powder, cinnamon, and salt. If using chocolate chips, do not add them yet.
3. Pour the cake batter into the prepared mug. Place in the microwave and cook for 45 seconds at full power. Remove and use a fork to stir the batter until uniformly mixed again. This helps the egg disperse, not settle to the bottom, and avoids rubbery results. If adding chocolate chips, add now and briefly stir to disperse.
4. Return to the microwave and cook 45-60 seconds more. There will still be a little moisture at top, and that is fine. It will absorb as it sits for 1 minute before serving. Avoid over cooking for best texture.

Recommended oats or using oat flour

Since oat mug cakes have a short cooking time, it’s essential to use fine, smaller, quick-cooking oatmeal for the fluffiest results. Quick oats absorb the liquids better in the short cooking time.

Another option would be to substitute an equal amount of oat flour. An oat flour mug cake would have an even more cake-like texture, so if you have it on hand, give it a try!

If you don’t have any in your kitchen, you can still easily make it in seconds, though. Place ½ cup quick or rolled oats in a blender. Blend for 30-45 seconds, or until no large flakes appear. Voila! Replace for the oats to make an oat flour mug cake in minutes!

How to Avoid rubbery mug cakes

Most mug cake recipes require an egg, which can become rubbery when cooked in the microwave. So how can we avoid this unpleasant texture in an oatmeal mug cake?

Easy! To avoid a rubbery cake, use a fork and stir the batter halfway through cooking. This will evenly distribute the egg throughout and absorb into the other ingredients. Also, be sure to not overcook, which causes too much moisture to evaporate.

Mug Cake Toppings

For best taste, enjoy warm out of the microwave oven. To make this a truly decadent dessert, top with one of the suggested toppings below. To serve for breakfast, choose healthier options such as fruit or nuts.

While the single serving size helps portion control, it can easily be divided into two servings, especially when adding toppings.

• Peanut butter or any preferred nut butter
• Sliced bananas
• Ice cream
• Fresh berries, such as strawberries, blueberries, or raspberries
• Nuts, such as almonds, walnuts, or candied pecans
• Whipped cream
• Chocolate sauce or hot fudge
• Coconut
• Quick glaze frosting – mix together 1 tbsp powdered sugar, 1 tsp milk, dash of vanilla extract.

Helpful tips To Remember

1. Make sure you have at least a 10 ounce mug or ramekin to cook the cake in. Of course, it should be microwave-safe!
2. Stirring the cake halfway through cooking ensures the egg doesn’t settle to the bottom and yields fluffier results.
3. If you would like to double the recipe and make 2 servings, use separate mugs and cook separately, not at the same time.
4. The oil may be replaced with an equal amount of creamy peanut butter, or any preferred nut butter. The cake will be slightly more dense, not quite as fluffy, but still delicious.
5. For leftovers, after it has cooled, wrap securely. For best results, rewarm slightly before enjoying again.
6. Looking for a larger cake to serve more people? Try this 5-minute blender oat flour cake with brown sugar frosting!

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