In a large bowl, microwave black beans for 1 minute, or until softened. Add roasted red peppers, garlic powder, paprika, cumin, and flax egg. Mash until black beans are finely mashed. Add flour and mix until thoroughly combined. Using a ½ cup (120 ml) measuring cup, portion 5 patties from the mixture. Place onto a lightly greased parchment paper-lined sheet pan. Bake for 30 minutes, or until firm and browned, flipping over halfway through.