Place a 12-inch cast-iron skillet over medium-high heat and 1 tablespoon of olive oil. Once hot, cook the onion with the turkey, cumin, and chili powder until browned, stirring frequently, about 10 minutes.
Add the corn, salsa, and black beans to the skillet. Stir to combine and cook until heated through, about 5 minutes. Remove from the heat.
Prepare the cornbread mix according to the package directions. Then pour the mixture evenly over the top of the turkey mixture and spread it out to cover the top.
Bake for 15 minutes. Sprinkle the shredded cheese all over the top of the cornbread and cook for an additional 5 minutes. Remove from the oven and serve warm.
Notes
If you don't have an oven-safe skillet available, transfer the turkey mixture to a 9x13 baking dish after cooking everything. Then pour the cornbread mixture over the top and continue as directed.
Nutritional information is based on using Famous Dave's original cornbread mix.