Cut broccoli into florets and pulse in a food processor until finely chopped then transfer to a large mixing bowl.
Chop and sauté spinach on a hot skillet with 1 Tbsp oil for a few minutes or just until soft, then add to the same mixing bowl.
In the bowl of a food processor (or using a meat grinder), grind together buckwheat and chicken breasts then transfer to the mixing bowl.
Finely dice/mince onion (a food processor makes it easy) and add to the mixing bowl.
Finally, add 1/4 cup panko bread crumbs, 1 egg, and 1 Tbsp of sour cream or mayo. Season with salt and pepper to taste (we used 1/2 tsp salt, 1/4 tsp pepper) then thoroughly mix until combined.
Form oval patties, dip them on both sides in Italian bread crumbs and cook on a well-oiled skillet over medium heat, flipping 4-5 times during the process until cooked through.
