Preheat oven to 350 degrees F (175 degrees C). Grease and flour an 8x8 inch baking pan.
In a large bowl, whisk together the PBfit powder, plant-based milk, applesauce, peanut butter, and maple syrup until smooth.
In a separate bowl, whisk together the gluten-free flour, baking powder, and baking soda.
Add the dry ingredients to the wet ingredients and stir until just combined.
Pour the batter into the prepared baking pan and bake in the preheated oven for 25-30 minutes, or until a toothpick inserted into the center comes out clean.
Let the bars cool completely before cutting into squares and serving.