Cut corn from the cob in a wide shallow bowl.
Saute corn, zucchini and onion in a skillet with a drizzle of olive oil until onion is transparent and zucchini is soft. Season with salt and pepper. Cover veggies briefly with a lid to soften zucchini if necessary.
Line a baking sheet with foil and spray with olive oil.
Spread 4 tortillas with a layer of refried beans, leaving a 1/4″ border {you might not need the whole can}, and place on prepared baking sheet.
Top with corn and zucchini mixture {you might have some left, save for a casserole, soup or salad}
Top with 1/4 of cheese.
Spread remaining 4 tortillas with a little sour cream and sprinkle with taco seasoning.
Invert and place on top of veggie stack, sour cream side down.
Spray quesadillas with olive oil spray. Can be refrigerated at this point for up to 8 hours.
Bake at 400 for 15-20 minutes until golden and heated through.
Let cool 5 minutes before slicing. Makes 4. Serve 1 whole one for main dish, 1/2 for appetizers.