Preheat your oven to 400°F (200°C).

In a skillet over medium heat, cook the sausage until browned and cooked through. Drain any excess grease and set aside.

In a large bowl, combine the diced potatoes, cooked sausage, ranch dressing mix, olive oil, salt, and pepper. Toss everything well to ensure the potatoes are evenly coated.

Spread the potato and sausage mixture evenly in a greased baking dish.

Pop the dish in the oven and bake for about 35-40 minutes, or until the potatoes are tender and golden brown.

After the baking time, remove the dish from the oven and sprinkle the cheddar cheese on top. Return to the oven and bake for an additional 5-7 minutes, or until the cheese is melted and bubbly.

Take it out and let it cool for a few minutes. Garnish with fresh parsley if desired, and then serve hot.