Preheat the oven to 350 degrees F. Grease an 8-inch square deep-sided baking pan.

Whisk ¾ cup of the flour and the sugar in a medium bowl. Cut in the butter with a pastry blender or two forks used scissor style until mixture resembles coarse crumbs. Set aside ½ cup of this mixture for the topping.

Add 1 cup of flour, baking powder, baking soda, cinnamon, and nutmeg. Mix well. Add eggs, milk and banana, mix just until incorporated, careful not to over mix.

Toss the blueberries with the remaining 1 teaspoon of flour. Stir them in along with the walnuts.

Pour into the prepared pan and sprinkle reserved topping evenly over top.

Bake 40 to 45 minutes until a toothpick in center comes out clean. Cool on wire rack.