This Oatmeal Mug Cake is ultra soft, light and fluffy with chewy bits of rolled oats. Made without any eggs, it's absolutely amazing any time of the day.
My top tips - Use rolled or old fashioned oats and not quick cooking or instant oats and enjoy hot. Continue for more!

I wanted a soft, and not dense cake made using rolled oats. I played around with proportions of oats to flour, to keep the cake from collapsing or becoming gummy.
Oatmeal mug cake is a healthy after school snack or a light breakfast made from oats, flour, milk, and other kitchen staples. Instant pot oatmeal has a creamy porridge consistency, but this recipe is like an oat muffin that's ready in in under 5 minutes.
Unlike a traditional oatmeal cake, stirring dry rolled oats without any hydration, minimized the released starch, thus resulting in a light texture.
You can top with berries or sliced bananas and walnuts for a tasty topping. If you have ever craved eating a dessert for breakfast like this air fryer bread pudding, then this recipe is for you.
Like the oats recipes that aren't oatmeal , oats mug cake made in microwave is a fun way to incorporate rolled oats into your diet beyond traditional oatmeal.
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Reasons to love it
Texture: Soft, light, and fluffy with a hint of chew from the rolled oats.
Quick and easy: If you are craving an oatmeal cake, then it can't get easier than this!
Not too sweet: Brown sugar adds just the right touch of caramel flavor without overpowering the sweetness.
Perfect any time of the day: Perfect for a light breakfast, late-night snack, after-school treat, or even a sweet post-dinner dessert.
Featured comments
From Karo: "made this lovely mug cake for the first time and let me tell u it’s the most delicious mug cake i’ve eaten. just perfect, and a perfect portion as well."
From Aeryn: "Super tasty and easy to make!
I was worried that it would be a little bland since the only flavouring is a ¼ teaspoon of cinnamon but I really enjoyed it. I made it in a bowl and did it for 10 seconds less and it worked perfectly, doesn't even need any toppings but it's still nice to add."
Table of contents
Ingredients You’ll Need
Scroll down to the recipe card below for full information on ingredients and amounts.
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- Oats - Old-fashioned style rolled oats are the best.
- Flour - All purpose flour gives stability to ensures the oats don't sink to the bottom.
- Sugar - We used golden brown sugar for caramel notes and moisture.
- Milk - Milk softens the oats and keeps the cake soft.
- Oil - A couple of tablespoons of vegetable oil prevents the dish from tasting rubbery.
- Baking powder- Baking powder prevents the oatmeal mug cake from tasting dense and lifts it all up!
Pro tip: This oatmeal mug cake recipe calls for using rolled or old fashioned oats. Quick cooking oats is much thinner and steel cut is hard to cook in the short microwave cooking time.
Add-ins
- Stir a tablespoon of semi sweet chocolate chips into the batter like in banana mug cake.
- Switch up the flavoring and use vanilla extract instead. Fall spices such as ground ginger, nutmeg or pumpkin spice can also be mixed along with cinnamon.
- Stir a tablespoon of golden raisins like in the best carrot mug cake recipe.
How to make oatmeal mug cake in microwave?
You can find full printable recipe below, but here is a quick overview of the procedure along with step-by-step photos.
👉 Tip: Cooking time will depend on the size of mug used. Wider mug will require slightly shorter time (1 minute + 40 seconds), whereas narrow mug will need about 10 seconds more (1 minute + 50 seconds).
👩🍳 Pro tip: For the best oatmeal mug cake texture, use whole oats and don’t over-cook. You want a deliciously soft & fluffy spoonful.
How to serve?
Serve for breakfast with a dollop of sweetened greek yogurt and some berries or sliced banana. Enjoy as a light dessert with sweetened whipped cream and Nutella.
Recipe tips
- Oats - Use only rolled or old fashioned oats for this recipe and not quick cooking or instant oats.
- Brown sugar - Golden or light brown sugar gives the perfect molasses taste.
- Stir batter until lump free – Using a spoon, stir the oatmeal mug cake batter until smooth and no lumps remain.
- Best eaten hot – Enjoy this cake HOT! As with mug cakes, some might dry out a little when left at room temperature.
- Type of mug to use - As with all mug cake recipes, any microwave safe coffee mug is best. The batter will rise significantly when cooking. So, make sure that mug is big enough.

More Mug Cake recipes
Oatmeal Mug Cake
Ingredients
- ¼ cup rolled or old fashioned oats
- 3 tablespoons all purpose flour
- 3 tablespoons light or golden brown sugar not packed
- ½ teaspoon baking powder
- ¼ teaspoon ground cinnamon
- 1 pinch salt
- ¼ cup milk whole or 2%
- 2 tablespoons vegetable oil
Toppings (optional)
- Sweetened greek yogurt or whipped cream
- Fresh berries
Instructions
- Add first 6 ingredients (oats, flour, brown sugar, baking powder, cinnamon and salt) into a microwave safe mug and stir well.Pro tip: This oatmeal mug cake recipe calls for using rolled or old fashioned oats. Quick cooking oats is much thinner and steel cut is hard to cook in the short microwave cooking time.
- Mix in milk and oil, until smooth and well combined.
- Microwave for 1 minute plus 40 seconds (if using a wide mug) or 1 minute plus 50 seconds (if using a narrow mug).Tip: Don't open the microwave while it's cooking.
- Remove mug from microwave, top with desired toppings and enjoy hot. Microwave cakes tends to get a little dry after some time.
Notes
Nutrition
Nutritional information, based on third-party calculations, should be seen as estimates, not guarantees, as various factors like product types, brands, processing methods, and more can alter the nutritional content in recipes.
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Barbara
Dear Maria, what is the wattage of your microwave? Since you can't open the microwave in between, and the 1m 40s time seems long for 1100 watts, I'm not sure how to make it in my microwave.
Maria Doss
Hi Barbara,
We apologize for a late reply. When cooking for the first time, we recommend checking after 1 min and 30 seconds. If it doesn't look well risen and cooked through, then cook for an additional 10 to 20 seconds. Hope it helps, have a great weekend - Maria
Caroline
I tried this today. The overall consistency was good but I found the hard bits to be disruptive (I would prefer plain porridge to this). Not my cup of tea, but not a bad recipe either 🙂
Maria Doss
Hi Caroline, Hmmm.. not sure about the crunchy bits you are talking about. Did you use steel cut oats instead of rolled oats? Regular oats will soften during the cooking time and will add to the texture but not stay crunchy - Maria
Cedric
Tried it out, added like 1 1/2 tbsp of "hand-crushed walnuts" for crunch - pretty good! Quick to make in a pinch, smooth and tasty, very muffin like. I might cut back by half a tablespoon of sugar next time and make my pinch of salt smaller (i did a tad less than 1/4 tsp and it was tasty, but a bit heavy on the palate). I mostly eyeballed (~2 min) the microwave since mine is from the 80's and isn't digital.
Maria Doss
That’s so great to hear! So glad you enjoyed it hun and thanks for the details – Maria ♡
Jay
Great recipe! Since I didn't have any brown sugar, I used coconut sugar instead and used only half as much. Instead of vegetable oil, I used avocado oil.
Maria Doss
hat’s so great to hear! So glad you love it – Maria ♡
Ann C
I've been making quite a few mug cakes lately. This one was very good! I agree with Cedric to cut back on the sugar next time. A half tablespoon less sugar is a good idea. Other than that, I loved the flavor and chewy texture of the cake. I might try letting it sit for an additional minute after mixing the dry and wet ingredients together and see if I like it less chewy. Thank you!
Maria Doss
Appreciate the feedback Ann, thanks for trying - Maria
karo
made this lovely mug cake for the first time and let me tell u it’s the most delicious mug cake i’ve eaten. just perfect, and a perfect portion as well.
Maria Doss
That’s so great to hear, so glad you loved it - Maria ♡
Aeryn
Super tasty and easy to make!
I was worried that it would be a little bland since the only flavouring is a ¼ teaspoon of cinnamon but I really enjoyed it. I made it in a bowl and did it for 10 seconds less and it worked perfectly, doesn't even need any toppings but it's still nice to add.
Maria Doss
That’s so great to hear, so glad you loved it - Maria ♡
Maria Doss
That’s so great to hear, so glad you loved it - Maria ♡