Preheat oven to 400F. Line a baking sheet with aluminum foil. Wash sweet potatoes and scrub thoroughly to remove any excess dirt. Dry completely.
Poke sweet potatoes all over with a fork and set on baking sheet. Bake at 400F for 45-50 minutes, until sweet potatoes are tender and easily pierced with a fork.
While the sweet potatoes are baking in the oven, preheat a large skillet over medium heat with olive oil or avocado oil.
Add turkey and onions and cook over medium heat, breaking up the turkey as it cooks. Cook for 8-10 minutes, until turkey is browned and no pink remains. Drain any extra fat.
Add water and spices to the skillet and stir to combine. Cook for 2-3 minutes, until water is absorbed by the meat. Remove from heat and set aside.
Make the guacamole just before serving. Mash the avocado with a fork. Add in cilantro, salt and lime and stir to combine. Taste and adjust any seasonings to your preferences.
To assemble, cut the warm baked sweet potatoes down the center lengthwise. Fill with taco turkey meat. Top with diced tomatoes, guacamole and additional cilantro. Serve immediately or store separately in airtight containers in the refrigerator until ready to reheat and eat.