Preheat your oven to 400 degrees Fahrenheit. Pierce the sweet potatoes several times with a fork, place them on a baking sheet, and roast for 45-60 minutes until very tender when pierced with a knife. Let cool completely, then remove the skins and mash the flesh in a large bowl with a fork until smooth.
Add the olive oil, cumin, chili powder, salt, pepper, black beans, corn, green chiles, red onion, and cilantro to the mashed sweet potatoes. Stir gently with a rubber spatula until all ingredients are evenly combined.
Lay a tortilla flat on a clean work surface. Spread 1/2 cup of the sweet potato filling evenly over one half of the tortilla, then sprinkle with 3 tablespoons of shredded cheese. Fold the other half of the tortilla over the filling to create a half-moon shape. Repeat with remaining tortillas and filling.
To freeze, place the assembled, uncooked quesadillas in a single layer on a parchment-lined baking sheet and freeze for 1 hour until firm. Transfer the frozen quesadillas to a large freezer bag or airtight container, separating layers with parchment paper.
To cook from frozen, heat a large skillet or griddle over medium heat and lightly coat with cooking spray. Cook each quesadilla for 3-4 minutes per side, pressing down gently with a spatula, until the tortilla is golden brown and crisp and the filling is heated through.
