Preheat oven to 400°F.
Place the sweet potatoes in a greased 9×13-inch baking dish. Toss with olive oil, salt, and pepper. Spread in an even layer, it’s ok if some of the potatoes are overlapping a little. Roast for 20 to 25 minutes, tossing once halfway through, until tender.
Meanwhile, heat a large skillet over medium heat. Add the ground turkey, onion, and bell pepper. Season with salt and pepper. Cook, breaking up the meat, until the turkey is cooked through, and the vegetables are softened.
Stir in the garlic and cook for 1 minute. Add the fire-roasted tomatoes, black beans, and taco seasoning. Stir to combine and simmer for 5 minutes. Remove from heat and stir in the cilantro.
Spoon the turkey and bean mixture evenly over the roasted sweet potatoes in the baking dish. Sprinkle with cheese.
Bake for 10 minutes, or until the cheese is melted.
Top with cilantro, avocado, and jalapeño ranch. Serve warm.
