Really Good Gluten Free Blueberry Banana Cake

Woke up this morning with a couple overripe bananas and a desire for something sweet to go with my tea. So I made this delectable and easy cake. You can make it into a loaf or muffins if you prefer.

Streusel Topping
6-7 tablespoons unsalted butter
1 cup gluten-free all purpose flour
½ cup sugar
½ teaspoon ground cinnamon
¼ teaspoon baking powder
¼ teaspoon salt
3 tablespoons walnuts or pecans, finely chopped

Place the butter in a heavy bottomed 2-qt saucepan and heat until almost melted; remove and cool to tepid. Meanwhile, whisk together the flour, sugar, cinnamon, baking powder, salt and nuts. Add to the butter and stir with a fork until blended and mixture begins to form crumbs. Gently squeeze the mixture with your hand to form larger lumps, then break them apart with your fingertips. Before using, let the streusel stand 10-15 minutes.

Note: This makes quite a bit of topping. I used some of it. The rest will keep in the fridge indefinitely.

Cake

1 cup almond meal
¾ cup gluten-free all purpose flour
½ teaspoon baking powder
½ teaspoon salt
¼ teaspoon baking soda
⅔ cup butter, room temp (or 7 T canola oil)
2 teaspoons lemon zest (opt)
½ cup brown sugar
1 large egg
1 teaspoon vanilla
½ cup buttermilk, (or milk with 1 T lemon juice)
2 ripe bananas
¾ cup fresh blueberries (opt)
¾ cup walnut pieces (opt)

Prepare a recipe of Streusel Topping and set aside.
Heat oven to 350º. Grease cake pan, loaf pan or line muffin tins with cupcake liners.

In a large bowl, thoroughly whisk the dry ingredients together. Set aside.

In another large bowl, cream together butter & optional lemon zest. Add sugar, blend, followed by the egg and vanilla. Reduce mixer speed and add flour mixture, alternately with buttermilk, starting & ending with the flour (3 flour, 2 buttermilk additions). Mix just until blended after each addition. Blend in mashed banana. Fold in blueberries.

(Note: I used oil instead of butter and didn't really need to use a mixer. A whisk and a spoon worked fine.)

Pour the batter into a 9x9 cake pan. Top with streusel mixture, completely covering the tops. Press gently to adhere.

Bake for 25-30 minutes or until the topping is golden brown. Remove from oven and place on a rack to cool.

To make a loaf instead, put in a loaf pan and bake at 325º for about 45 min to 1 hour. Or for muffins pour batter into muffin tin and bakeat  375º for about 25 minutes. Test middle for doneness before removing.