2. Add the vanilla protein powder, almond flour, oat flour, baking powder, and a pinch of salt to the bowl. Mix everything together using a whisk until you have a smooth batter.

3. Gently fold in the frozen blueberries using a spatula. Be careful not to overmix; you want the blueberries to be evenly distributed throughout the batter.

4. If your cake pan is not made of silicone, generously grease a 20 cm (approximately 8-inch) cake pan to prevent sticking.

5. Pour the prepared batter into the greased cake pan.

6. Preheat your oven to 180 degrees Celsius (approximately 350 degrees Fahrenheit).

7. Bake the cake in the preheated oven for approximately 50 minutes or until a toothpick inserted into the center comes out dry. Baking times may vary slightly depending on your oven, so keep an eye on it.

8. Once the cake is done, remove it from the oven and allow it to cool in the pan for a while before transferring it to a wire rack to cool completely.

9. Once cooled, slice, serve, and enjoy your delicious blueberry ricotta cake!