Filed under: Gluten-free / Muffins
October 20, 2022

Oat Flour Banana Muffins

One bowl, overnight super soft banana muffins made with oat flour. 

5 from 9 votes
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If you’ve been here a minute, you’ve heard seen me extoll oat flour ad nauseam. I think it makes cookies chewier (and more flavorful) and blondies as well.  I use it when I make pancakes or waffles and happily substitute it in my quick breads and muffins. I also have an oat flour brownie recipe which I promise will be up here someday too. 

But truthfully, these started out – as all good banana bread recipes do – as a way to use up browning bananas. I wanted a recipe that was fit for morning: I could prep it the night before (with minimal effort), stick it in the fridge and bake some tall, domed lovely muffins in the AM. And oat flour came about because, well – it just worked *so* perfectly here. 

Truly this is another magic recipe: it’s one bowl, it sits in the fridge where the dough thickens and chills, then you bake it and you have the softest most lovely banana muffins. 


Recipe Ingredients 

Bananas: very ripe, covered in brown spots and mushy!

Oat flour: I use storebought (more on using homemade below) as it’s fine. Oat flour is naturally gluten free.

Eggs: whole large eggs. No need to bring them to room temperature.

Sugar: brown sugar, light or dark, adds more moisture to the batter and better flavor.

Oil: any flavorless oil like avocado or grape seed or canola.

Cinnamon: If you’re allergic, try cardamom or just leave it without any spice. It’ll still be great. 

Sour cream: I use full fat. Substitutes can be labneh, greek or regular yogurt, vanilla or plain. 

How to make Oat Flour Banana Muffins

Mash the bananas then add them, the flavorings, the sugar and oil to a bowl.

Whisk everything together. Don’t worry about breaking up the banana bits, we’ve got more mixing to do

Add the eggs and whisk to combine then add the flour and stir – don’t over do it once the flour is in, just enough to see there’s no dry flour bits remaining

Add chocolate chips if you like (I was under strict instruction to add them for this particular batch) and cover the bowl for the resting period

The batter can be kept overnight in the fridge to bake in the morning.

Bake until tops spring back or a cake tester comes out clean.

Recommended add-ins and toppings 

Let’s be real, these are best as is, warm, sliced in half and smothered in a pat of butter but if you are feeling like you want something extra, I have a few suggestions: 

A nutella swirl. Warm a few tablespoons of nutella in the microwave. When you’ve got the batter in the muffin liners, dollop about a teaspoon of nutella on top then use a toothpick to swirl it with the batter. 

Nuts and chocolate chips. Any nut, any chocolate chip! For nuts, toast them and let them cool before adding to the batter. 

Glaze. I made a glaze with 1 cup powdered sugar, a pinch of vanilla, a dash of vanilla paste and 2 tablespoons of milk. 

Can I make these overnight oat banana muffins with homemade oat flour? 

So I’ve heard from people who have tried this in my other recipes (like my oat flour blondies) and they’ve managed to do so successfully. I have never had such luck; perhaps my food processor isn’t strong enough but when I compare store-bought oat flour to home-ground, the latter is an even, fine powder. 

So to answer the question, I’d say if you’ve done it successfully before go for it. If not, stick to store-bought. 


Can I halve these for a small batch of oat banana muffins? 

You sure can! It’ll make six so you’ll only need one 12-cup muffin tin. 



Overnight Oat Banana Muffin Recipe (Gluten-Free)

Oat Flour Banana Muffins

One bowl, overnight banana muffins made with oat flour.
Prep Time: 10 minutes
Cook Time: 18 minutes
Chill Time: 8 hours
5 from 9 votes


  • 3or 300g overripe bananas
  • 1cup or 215g brown sugar
  • ½cup or 100g canola or olive or avocado oil
  • ¼cup or 60g sour cream
  • ¾ tsp fine sea salt
  • 2 large eggs
  • 2cups or 270g oat flour
  • 1 tsp baking soda
  • 1 tsp ground cinnamon
  • 1 tsp pure vanilla extract


  • Mash the bananas then whisk them with the sugar and oil. Add in the salt, vanilla, cinnamon, and sour cream and whisk well. Whisk in the eggs.
  • Add the flour and baking soda and fold with a rubber spatula until combined. Cover with plastic wrap and set in the fridge overnight (or at least for 4 hours).
  • When you are ready to bake, preheat the oven to 400 F. Line two 12 cup muffin tins with six liners each, alternating cups so that no two muffins will bake next to each other.
  • Bake for 20 minutes, until the tops spring back when pressed.


Makes one dozen muffins

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Recipe Reviews

  1. 5 stars
    I love the versatility of these muffins. They don’t taste too much like banana, which I like. I use “homemade” oat flour, which results in a denser muffin. I’ve made them several times, including making them less fattening by subbing flax seed for the egg and applesauce for the oil.

  2. 5 stars
    A lovely muffin! They are quite dense but must be a result of the oat flour which I’ve never used before. I really like the flavor and texture. Next time I’ll add in some nuts, possibly a few blueberries and a cinnamon sugar sprinkle on top. Overall, an easy 1 bowl recipe anyone can whip up for an easy and delicious muffin!

  3. My third time around I also omitted a portion of the sugar—which I’ve never done in any recipe before, and the choice was down to curiosity, not any health-related reason nor do I think the recipe as you’ve developed it calls for too much sugar. I replaced the banana with a combination of chunky cooked sweet potato puree and a 1/4ish cup raw grated sweet potato. I don’t actually care for sweet potatoes generally but I had them and needed to use them.

    I think I’m a sweet potato lover now! End result had a really nice flavor and mellowness and the breakfast-y aspect made them more satisfying than the dessert-oriented quickbread batters I normally prefer.

    I’m thinking of toasting the oatflour next time. Any thoughts about whether this will produce even oatier flavor, or will ot get lost in the mix?

  4. 5 stars
    An easy comforting breakfast. What’s not to like? The oat flour helps lend a little nuttiness to the batter and the muffins were super tender. Flavor was on point! The batter was super quick to whip up the night before. I added some walnuts and it was superb. These will become my new routine banana muffins!

  5. 5 stars
    These are perfect! So soft and moist, nice flavour. I refrigerated the dough for 24 hours because that was how the timing worked out for me, and I added 1/2 cup semi sweet chocolate chips. Made 13 nice sized muffins. Will definitely be making these again soon. Great after school snack or breakfast for the kids!

  6. 5 stars
    These came out really well! I had an extra banana that needed to be used, so I put it in and subtracted the equivalent amount (by weight) from the sugar. I was worried this would give me a poor result, but they looked and tasted great (I’m sure mine are less sweet tasting than Sam’s). I added walnuts and yielded 14 muffins.

  7. 5 stars
    made them twice with chocolate chips already, cut down the sugar by 50gr in the second batch cause i like it less sweet but both batches were perfect with the nicest tall domes and remain moist and soft for days. soo good 🙂