Preheat oven to 400°F (200°C).

In a large bowl, thoroughly mash bananas with the back of a fork. Stir in protein powder, oats, milk, cinnamon, baking powder, and half of the vanilla extract (reserving the other half for later). Mix until well incorporated.

Transfer mixture to a greased baking dish and bake for 20 minutes. (Size of baking dish needed and time can vary depend on how much the original recipe has been scaled. Mixture should be approx 1in (2.5 cm) thick in dish. Adjust cook time if necessary).

Meanwhile, make the 'frosting' by mixing together the cream cheese, yogurt, maple syrup and remaining half of vanilla. Stir well until no lumps remain.

Remove the dish from oven and let cool. Cut it into the number of bars listed in the recipe details above. Frost then serve.

Meal Prep Tip: A. Store bars and frosting in separate air tight containers in the fridge. When ready to eat, you can microwave the bars for a few seconds to slightly warm them up, and then frost. B. Another option is to swirl the frosting it in the raw batter and bake it into the bars. Then there is no need for the separate storage of the frosting and it's easier to transport.

Put all ingredients in a blender.

Mix until well-blended. Add more water depending on your preferred consistency.

Serve immediately.