1. Preheat oven to 325. Brush tortillas with olive oil on both sides and place on baking dish. Bake for 20 minutes, turning once after 10 minutes.
2. Combine yogurt, lime juice, water, and green onions. Season with salt + pepper.
3. Pierce sweet potato several times with a sharp knife, wrap in paper towel, and microwave on high 7-9 minutes (depending on size) until tender and cooked through. Set aside to cool.
4. While sweet potato cooks and cools, heat a tablespoon of olive oil on medium-high, add zucchini and sauté until lightly brown. Add corn and cook for an additional 1-2 minutes on medium. Reduce to low to keep warm.
5. Remove sweet potato flesh, add greek yogurt, garlic, salt, pepper, and cayenne and mix to combine.
6. Top tortillas with sweet potato puree, black beans, vegetables, and drizzle with lime cream. Garnish with cilantro and/or favorite toppings.