In a food processor, combine most of black beans (you can eye ball it) and sweet potato puree. Pulse until mostly smooth. Transfer mixture to a medium-sized bowl, add remaining black beans (for added texture).
Add flaxseeds, chia seeds, sriracha and spices. Mix to combine.
Refrigerate mixture for 10 minutes.
Preheat oven to 400°F. On a parchment paper-lined baking sheet, scoop out 1/4 cup of batter. Flatten with the palm of your hand. Bake for 20 minutes, carefully flip burgers, and bake for another 15 minutes.
Serve on whole wheat bun, with lettuce, tomato, avocado, ketchup, mayo, etc, to your liking. Enjoy ?