In a bowl; add boiled potatoes and boiled chickpeas and mash them. I like to keep chickpeas a bit chunky since they taste good that way but if you prefer to mash it completely, go ahead.
1 cup chickpea, 1 onion
Add salt, pepper, cumin powder, minced garlic, chili powder, dry mango powder, and chopped fresh coriander. Mix well to combine.
Make round patties with the mixture and roll them on breadcrumbs to coat evenly. Put the mixture in the fridge for about 30 mins to rest and absorb the flavors.
Chop onions lengthwise. Saute onion for about 5 mins till caramelized on medium-high heat. Add bell peppers and saute for a couple of mins.
In the same pan; add 4-5 Tbsp oil. Reduce the heat to medium-low. Add patties and cook for 3-4 mins on each side.
SERVING:
Heat the burger buns in the same pan. Place the pattie, add onion and bell pepper mixture on it. Top with some spinach and your favorite sauce. I used cilantro dip instead of any sauce.