Spray 2½ quart casserole dish with cooking spray. (A 9x13 inch pan will work.)
Heat large skillet drizzled with olive oil (or cooking spray). Cook and break apart turkey.
Add in black beans, tomatoes, corn, zucchini, edamame, salsa and spices. Bring to a boil. Turn down heat, cover and simmer for 10 minutes.
Slice one tube of polenta and cover bottom of baking dish. *If desired fry polenta slices in a hot skillet about 3 minutes per side. Use cooking spray or olive oil.
Spread the meat and vegetable mixture over polenta.
Slice remaining tube of polenta spread evenly on top.