Preheat oven to 350 degrees F. Place the sweet potatoes (cut lengthwise) face down on a baking sheet. Brush the backs with olive oil and sprinkle on salt and pepper. Place in the oven for 30 minutes.
While potatoes are cooking, place ground beef in a large skillet and cook on medium-high heat, until browned. Add in spices and diced red pepper. Cook until bell pepper softens (3-4 minutes). Add a few tablespoons of water if needed to keep the meat from drying out.
To serve – use a fork to flatten the inside of the roasted potato slightly. Add the desired amount of ground beef mixture and top with fresh lettuce, chopped tomatoes, avocado, salsa, and cilantro.