These Blueberry Banana Oat Crumb Muffins make for a fantastic on-the-go breakfast or snack. Add walnuts for some extra crunch!

Blueberry Banana Oat Crumb Muffins | Killing Thyme

I had a completely different post scheduled for today. But then I made these muffins and changed my plan at the last minute in a fit of excitement because these. muffins. are. LIFE.

Nothing beats the smell of blueberries baking on a warm summer morning. Whether you’re incorporating them into pancakes or folding them into muffin batter, there’s something incredibly nostalgic about that warming berry aroma. And I had a strong hankering for that sense of nostalgia, so I decided that this was a great opportunity to make blueberry-filled muffins.

And to break up the army of brown bananas in my freezer.

I don’t bake often. That’s no secret. But when I do get around to it, I like to pretend that I know what I’m doing, and it usually works out pretty well in the end.

I found a good recipe for Banana Blueberry Crumb Muffins here and made a few alterations; I swapped the white sugar for maple syrup, the brown sugar for coconut palm sugar, I brought walnuts to the mix, and I added oats to the crumb topping.

Oh, I also replaced the usual old egg with a local duck egg from my friends farm over at Mabel’s Acres! But you can use a regular egg, of course.

Blueberry Banana Oat Crumb Muffins | Killing Thyme

Blueberry Banana Oat Crumb Muffins | Killing Thyme

Because my husband and I are savages, I take my muffins (and most of my baked goods) out of the oven about a minute or two early. We love the extra moistness and chewiness of slightly under-baked treats and it works oh-so-well with these bad boys.

But you do you. Bake them until they’re cooked through if that’s your jam.

Making this recipe? Snap a pic and tag me on Instagram: @Killing__Thyme /#killingthyme. For more delish eats, follow me on INSTAGRAM + PINTEREST.

Blueberry Banana Oat Crumb Muffins

These muffins are naturally sweetened and packed with warm blueberries, gooey bananas, and crunchy walnuts, then topped with an incredibly oat crumble.
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Prep Time: 15 minutes
Cook Time: 20 minutes
Total Time: 35 minutes
Servings: 12 muffins


  • 1.5 cup all purpose flour
  • 1 tsp baking soda
  • 1 tsp baking powder
  • 1/2 tsp kosher salt
  • 3 over-ripened bananas, mashed
  • 3/4 cup natural maple syrup
  • 1 egg beaten
  • 1/3 cup butter, melted
  • 1 cup fresh blueberries
  • 1/2 cup roughly chopped walnuts

Oat Crumb Topping

  • 1/4 cup coconut palm sugar you can use brown sugar
  • 1 TBSP flour
  • 1/4 tsp ground cinnamon
  • 1/2 TBSP butter
  • 2 TBSP rolled oats


  • Preheat the oven to 370 degrees F. While the oven heats up, line a muffin tin with liners.
  • In a large bowl combine, whisk together 1.5 cups of flour with baking soda, baking powder, and salt.
  • In a medium bowl, combine the mashed bananas, sugar, egg, and melted butter. Whisk well until thoroughly combined.
  • Slowly and gradually add the banana mixture to the flour mixture while stirring it, just until it's lightly mixed. Gently fold in the blueberries and the walnuts.
  • In a small bowl, combine the coconut palm sugar, 1 tablespoon of flour, ground cinnamon, and rolled oats.
  • With a fork, cut the 1/2 tablespoon of butter into the mixture until it's slightly crumbly.
  • Evenly spoon the muffin batter into muffin papers. Sprinkle the sugar topping over the tops of the muffins.
  • Bake for 18-20 minutes, or until a toothpick or cake tester is inserted into the center and comes out clean.
  • Once done, remove, set on a cooling rack, and let cool for 5-10 minutes.
Blueberry Banana Oat Crumb Muffins | Killing Thyme