Preheat the oven to 400°F.
Cook the sweet potatoes: pierce the sweet potatoes with a fork all over several times. Place on a baking sheet lined with aluminum foil; bake until soft and fork tender, about 45 minutes. (Or pierce with fork and cook in the microwave until soft & tender. I like to wrap mine in a paper towel. Cook time will vary based on size of the sweet potato but you can start with 10 minutes.)
Heat the olive oil in a deep skillet over medium heat. Add in the onions, bell peppers and garlic; cook, stirring occasionally, until tender, ~5 minutes. Stir in the red pepper chili flakes, cumin, garlic powder, oregano and salt.
Add the ground turkey; cook, stirring and breaking it up with a spoon, until no longer pink, ~3 to 5 minutes. Stir in the tomatoes. Reduce the heat to low; cover and cook for 10-15 minutes.
Remove from heat. Slice the baked sweet potatoes lengthwise just until open. Fill with the turkey mixture. Top with cheese & avocado.
Alternatively, you can scoop the sweet potato out into a bowl and build bowls instead of eating from the sweet potato itself. Enjoy!