Preheat the oven to 375°F (190°C). Lightly coat a baking dish with cooking spray or a small amount of olive oil.

Bring a large pot of water to a boil. Carefully add the sweet potato slices and parboil for about 8 minutes, or until slightly tender while still firm enough to hold their shape. Drain well and set aside.

Heat a little of the olive oil in a large skillet over medium heat. Add the spicy beef sausage and break it into small pieces with a wooden spoon. Cook for about 8 minutes, or until browned and completely cooked through. Remove from the heat.

Place the sliced apples in a bowl. Toss with 1 teaspoon cinnamon, a pinch of salt, black pepper, and a small drizzle of olive oil until evenly coated.

Arrange half of the sweet potato slices across the bottom of the prepared baking dish. Add half of the cooked beef sausage, followed by half of the seasoned apples and some of the chopped pecans.

Repeat the layers with the remaining sweet potatoes, sausage, apples, and pecans.

Sprinkle the shredded cheddar evenly over the top. Cover the baking dish loosely with foil.

Bake the Sweet Potato and Sausage Casserole for 30–35 minutes, removing the foil for the final 5 minutes so the cheese can become bubbly and lightly golden.

Remove from the oven and allow the casserole to rest for about 5 minutes before serving.