Preheat the oven to 375 degrees. Heat the oil in a large, deep skillet over medium-high heat. Add the zucchini and saute. Add bell pepper, then corn to the pan and continue to saute until the veggies are soft, 5-10 minutes. Remove from heat.
Once the mixture has cooled for a few minutes, stir in the cilantro, salt, and cheese. Line a pan with parchment paper or just grease a pan with nonstick spray. Transfer the mixture to the pan. Arrange the top so the zucchini slices lay flat and look nice. Top with a little extra cheese for looks, cover with greased foil, and bake for 20 minutes. Remove foil and bake for an additional 5 minutes to brown the top. Let stand for 10-15 minutes before cutting into slices.
It will bubble up a little bit as it bakes, so put a pan under to catch drips if it’s really full. Also, there was a little extra watery-ness (about 2 tablespoons) in the bottom of my pan when I sliced it, but the pieces held together perfectly so NBD. I think the moisture could be prevented by just being a little more patient before cutting.
I sprinkled mine with fresh herbs (parsley and cilantro) like I always do on everything. Basil would also be yummy.