Grease and flour a 7 inch spring form pan or a 6 cup Bundt cake pan.

In a 2 quart mixing bowl, add almond flour, gluten free flour, baking powder, and cold butter.  Break up the butter with a pastry cutter or two knives and blend it into the flour mixture, until it is the size of lentils.

In a separate bowl, add eggs, yogurt, and maple syrup.  Beat with a fork to blend well.

Make a well in the center of the flour mixture.  Pour in the prepared moist ingredients.  Mix well to get rid of any flour-y parts.

Add blueberries and mix gently to evenly distribute in the batter.

Spoon batter into prepared pan.

Topping:

Place pecans in a blender jar.  Blend until the pecan mixture resembles coarse crumbs.  Mix pecans, flour, and butter together until mixture is coarse and evenly textured.

Sprinkle over the top of the cake batter in the cake pan, in an even layer.

Bake in 350 F oven for 45 to 55 minutes.  Remove from oven when the cake tests done, and a toothpick inserted in the center comes out clean.  Allow the cake to cool on a rack for 15 minutes, before removing from the pan.  Cool completely before slicing.