Cook all the vegetables (except the onions) in a large pot covered by about an inch of water until soft (about 20-30 minutes).
Drain the vegetables then peel off the skin of potatoes and mash it well.
Add the other vegetables, the finely chopped onions, and breadcrumbs as well as all the spices and lemon juice. Mix well and mash slightly until doughy.
As if you were making burgers, make equal sized round balls and press between your palms to flatten.
In a small bowl mix cornmeal and water to form a thick paste then dip each cutlet in the "paste" such that both sides are coated well mixture and then coat it with breadcrumbs. Repeat for all of the other cutlets.
Either fry on the stove in a shallow pan or you can bake them at 350 for about 20 minutes in the oven.