Preheat the oven to 425°F (220°C). Peel and dice the sweet potatoes into 1/2-inch cubes. Place them on a baking sheet, drizzle with 1 tablespoon of oil, and season with salt and pepper. Toss to coat evenly. Roast for 25-30 minutes or until tender and slightly caramelized, flipping halfway through.

While sweet potatoes are roasting, finely chop the onion and mince the garlic. Heat a large skillet over medium-high heat with 1 tablespoon of oil. Add the onion and garlic, cooking until softened, about 3 minutes.

Add the lean ground beef to the skillet, breaking it apart with a spatula, and cook until browned. Drain excess fat if necessary. Stir in the cumin, chili powder, salt, and pepper. Cook for an additional 2-3 minutes to let the spices bloom.

Reduce oven temperature to 375°F (190°C). Pour 1/2 cup of enchilada sauce into a 9x13 inch baking dish, spreading evenly over the bottom.

Place a spoonful of the beef mixture and some shredded cheese in each tortilla, then roll tightly and place seam-side down in the baking dish. Pour remaining enchilada sauce over the top of the enchiladas and sprinkle with the rest of the cheese.

Cover the dish with foil and bake in the oven for 20 minutes. Remove the foil and bake for an additional 10 minutes, or until the cheese is melted and bubbly.

While the enchiladas are baking, prepare the Mexican-style corn. In a separate skillet, melt 2 tablespoons of butter over medium heat. Add corn kernels and cook until charred and heated through, about 5-7 minutes.

Squeeze the juice of one lime over the cooked corn, and stir in chopped cilantro. Season with salt and pepper to taste.

Serve the beef enchiladas hot, with roasted sweet potatoes on the side and Mexican-style corn garnished with extra cilantro.