1/4 cup unsalted butter, softened
Preheat oven to 350F and grease a loaf pan.
In a medium bowl combine flour, ground almonds, baking powder, salt and cinnamon. Set aside.
With an electric mixer and a large bowl or in the bowl of a stand mixer fitted with a paddle attachment, cream together butter and sugar until well combined, about 3 minutes. Add eggs, one at a time, and mix until well incorporated. Add almond extract and bananas and mix to combine.
Gradually add the flour mixture to the banana mixture, and mix until just combined. By hand, stir in blueberries and mix until well distributed in the batter. Pour batter into prepared loaf pan and sprinkle top with sliced almonds. Bake for 40-45 minutes or until a toothpick inserted in the centre comes out clean.
Cool on a baking rack for 10 minutes in the pan then remove from the pan and cool completely.