Preheat Oven: Set it to 350°F (175°C) and prepare a 9-inch round cake pan with grease or parchment paper.
Mix Dry Ingredients: In a large bowl, combine 1 1/2 cups almond flour, 1/2 cup coconut flour, 1 tsp baking powder, 1/2 tsp baking soda, 1/2 tsp cinnamon, and 1/4 tsp salt.
Combine Wet Ingredients: In a medium bowl, whisk together 3 ripe bananas (mashed), 1/2 cup honey or maple syrup, 1/4 cup melted coconut oil, and 3 large eggs.
Mix Together: Blend the wet ingredients into the dry mixture. Stir until well combined.
Prepare Streusel: In a small bowl, mix 1/4 cup almond flour, 2 tbsp coconut sugar, 2 tbsp melted coconut oil, and 1/4 tsp cinnamon.
Assemble Cake: Pour the batter into the prepared cake pan. Sprinkle the streusel topping evenly over the top.
Bake: Pop it in the oven and bake for 40 minutes, or until a toothpick inserted into the center comes out clean.
Cool and Serve: Let the cake cool in the pan for 10 minutes before transferring to a wire rack. Slice and savor!