To prepare a french toast with mixed berries with Truvia natural sweetener recipe, preheat the oven to 450 degrees F (232 degrees C) and grease two 8-inch round baking pans with cooking spray. Whisk together the flour, baking powder, sugar, cinnamon, and salt. Pour the wet ingredients into the dry ingredients and stir to combine. Bake the French toast for 20 to 25 minutes or until the top is golden brown. Let the bread cool for 5 minutes before slicing and serving.