Preheat oven to 350°F/°176°C.

Scrub the potatoes and dry well. Pierce the skin all over with a fork. Place on a baking sheet and bake for 1 hour.

While the potatoes bake, make the sausage: To a large sauté pan, add the oil over medium heat. Add the sausage meat and brown, while breaking up the meat. Add the onion and continue to cook until the onions are softened. Stir in the garlic and oregano and cook for 1 minute stirring. Add the crushed tomatoes and stir. Simmer for 10 minutes until thickened, turn off the heat. Taste for seasoning, add salt if needed (this depends on how salty your sausage is).

To a microwave-safe bowl, add the butter and 4 tablespoons Parmesan cheese. Loosely cover and microwave for 20-30 seconds until melted, mix well.

When the potatoes are done (a sharp knife should insert easily) cut a slit down the potato lengthwise. Use a fork to fluff up the potato.

Drizzle the melted butter and Parmesan onto the fluffed potato, mixing with a fork to combine.

Top the potatoes with the meat sauce, grated Parmesan cheese and basil.