Using a sharp knife and a cutting guide, slice the zucchini into ¼" slices all along the length of the zucchini making sure not to slice all the way through.
Gently pry the slices apart (being careful not to break the zucchini) and stuff each of the cuts with a slice of pepperoni and a slice of provolone that has been cut into quarters.
Drizzle the stuffed zucchini with olive oil and season with salt and pepper.
Spoon the marinara sauce over the zucchini in the baking dish and top evenly with the grated Parmesan cheese.
Bake uncovered in a preheated oven for 30-35 minutes. Remove and cool for 10-15 minutes before serving.
Notes
I don't recommend freezing this completed dish as it will be mushy when thawed.Store leftovers in an air tight container in the refrigerator for up to 5 days.Reheat in a 350 degree oven or covered with plastic wrap in a microwave.