Preheat the oven to 400°F then place the diced sweet potato in a 9 x 13” casserole dish. Using your hands, toss the sweet potato pieces with one tablespoon of high heat oil until evenly coated. Bake in the oven for 25 minutes, until tender.Meanwhile, in a large bowl, combine the black beans, chopped spinach, corn, chopped bell pepper, jalapeño, sliced green onion and chopped cilantro . Once the sweet potato is done, reduce the temperature to 350°F then add the cooked potato to the bowl as well. Sprinkle in the spices and add the lime juice. Stir together until well combined. Lastly, add 1/2 cup of the cheese and stir to combine.Spread a thin layer of salsa over the bottom of the casserole dish and set aside. Scoop the vegetables into the tortillas one at a time so that it fills the center. If you position the filling at a diagonal angle to the tortilla, it makes it easier to roll up. Roll each tortilla then arrange them in the casserole dish seam side down.Once all of the tortillas are arranged in the dish, top with last of the salsa and sprinkle with remaining cheese. Cover the dish with foil and bake for 20 minutes. Remove from oven, uncover, then return to the oven and bake for an additional 15 minutes.Serve warm and garnish with diced avocado and/or cilantro. Leftovers can be stored in an airtight container for up to 4 days in the refrigerator. If you would like to freeze them, do it before adding salsa and baking.