What you need:
1-2 sweet potato
1-2 Mexican squash
Non-Fat Greek yogurt (in place of sour cream)
pinch of salt, pepper, and chili powder
In a cast iron skillet saute your peeled and diced sweet potato and diced Mexican squash in olive oil and your spices for about 2 min, then transfer to the oven at 350 for about 15min or until the sweet potatos are done.
Steam your corn tortilla and mash your avocado, assemble everything the way you like it and enjoy!