Mash the beans in the food processor or with the back of a fork and mix with the sunflower seeds. Mix in the remaining ingredients and form into 4 patties.
Place the patties on a parchment paper-lined or lightly-oiled baking sheet and bake for 25 minutes. Carefully flip burgers, reforming as necessary and bake for another 10 minutes.
Note: If desired, these may also be done on the grill. Place on a hot, lightly oiled grill over medium-low heat and cook for 6-8 minutes per side until heated through and lightly browned.