{Gluten-Free} Whole Grain Banana-Walnut Cake

One of my favorite cookbooks is Kim Boyce’s Good to the Grain, a beautiful volume full of rustic, homey desserts and breakfast bakes incorporating whole grains and some gluten-free flours. I made her banana walnut cake two years ago when we were just getting to know our neighbors, now good friends, down the street — they’d invited us for dinner and I brought dessert, glad to have the excuse to bake a cake I’d been eyeing for awhile. It was so well received I knew I had to adapt it to be gluten-free and lower in sugar.

This is a simple, nubbly cake full of bananas and ground walnuts, a perfect winter weekend cake. Baking with bananas is a bit of a sugar cheat — I love them because they can work to sweeten a batter without needing a lot of additional sugar. My Aussie friend Katie and I recently had a text conversation about the versatility and beauty of bananas and she reminded me that a banana can even work as an egg in a pinch. In this recipe I’ve kept them as a flavor and sweetness enhancer, but I will keep that info in my back pocket for another time.

This is a lovely cake to put together — you just need sorghum and arrowroot to form your flour base, then fold in some toasted, ground walnuts for texture and heft. Just one-half cup of sweetener is needed, so the additional sugar is turned way down (hooray!). Yet the cake is certainly sweet enough, and the natural goodness of the bananas keeps it tasting like a treat. You’ll want very ripe bananas here; you can freeze them until you’re ready to use, then defrost at room temperature.

If you don’t have sorghum you can swap gluten-free oat flour by weight, or any other gluten-free flour you like, though oat will be the closest in flavor profile.

Enjoy these winter days!

Til next time- N x

Whole Grain Banana-Walnut Cake

Recipe by Nicole Spiridakis



Inspired by a recipe in Good to the Grain, this banana cake is lovely with an afternoon cup of tea or even as a mid-morning snack.


  • 2 cups walnut pieces

  • 100 g (2/3 cup) sorghum flour

  • 60 g (1/3 cup + 1 Tablespoon) arrowroot

  • 1 Tablespoon baking powder

  • 1/2 teaspoon baking soda

  • 1/2 teaspoon fine sea salt

  • 4 oz (1 stick) unsalted butter, at room temperature

  • 1/4 cup coconut sugar + 1 teaspoon, divided

  • 1/4 cup maple syrup

  • 4 medium-large very ripe bananas

  • 3 large eggs

  • 1/3 cup Greek yogurt

  • 1 teaspoon pure vanilla extract


  • Heat oven to 350 F. Rub an 8 or 9-inch pan with butter and line with parchment. Spread walnut pieces on a baking sheet, place in the oven, and toast for about 10 minutes. Remove from oven and set aside to cool. Turn off oven.
  • In a medium bowl, sift together the sorghum flour, arrowroot, baking powder, baking soda, and salt. Place one cup of the toasted walnuts in a food processor and process until finely ground. Add to the flour mixture and stir to combine.
  • In a large bowl, using a mixer, beat the butter, 1/4 cup coconut sugar, and maple syrup together for a few minutes until light and fluffy. Add the bananas and mix on medium speed until the bananas are broken down and smooth. Scrape down the bowl as necessary. Add the eggs one at a time and beat until thoroughly combined. Add the Greek yogurt and vanilla and mix well to combine.
  • Pour in the walnut-flours mixture and mix on low speed until combined. If you can, let batter rest for 30 minutes. Finely chop the remaining 1 cup of walnut pieces.
  • Heat oven to 350 F, Scrape the batter into the prepared pan. Scatter the chopped walnuts evenly across the top of the batter, then sprinkle 1 teaspoon of coconut sugar across the walnuts.
  • Place pan in the oven and bake for 50-60 minutes, until a toothpick inserted in the center comes out clean. Remove pan from oven, place on a rack, and allow to cool in the pan before turning out. Cake can be kept well covered in the fridge for up to a week.
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