Place sweet potato in a container (I didn't add water in the container, but added in the cooker as usual). Pressure cook for 3 -4 whistles.
Meanwhile, boil water and add broccoli florets, cook for 2 mins. Drain water completely. (You can steam cook too couple of mins)
Grind in a blender coarsely. Just for few seconds, do not make into a paste. Squeeze the excess water from the ground broccoli.
Take one peeled sweet potato in a mixing bowl. Mash well without any lumps. (Approx. 1 cup mashed sweet potato)
Add ground broccoli, grated cheese, bread crumbs, turmeric, chaat masala, cumin powder, black pepper and salt. Mix to a dough.
Divide into equal portions and make equal sized balls out of it. Flatten to a tikki/ patty.
Heat a pan with few drops of oil and place the tikkies over it. Cook over medium flame both sides until golden layer forms.