Preheat oven to 400°F.
Slice the sausages. Peel and finely chop the onion and garlic.
Heat the olive oil in a large baking dish or skillet on the stovetop. Sauté the sausage slices for 2–3 minutes until lightly browned. Add the onions and garlic and sauté briefly until fragrant.
Pour in the diced tomatoes, broth, and heavy cream. Season with paprika, oregano, salt, and pepper. Stir well.
Place the uncooked spaghetti directly into the sauce and gently press it into the sauce so that it's completely covered. If necessary, add a splash more water.
Place the dish in the oven and bake for about 30 minutes. Give it a stir every 10 minutes so the spaghetti cooks evenly. If you notice your dish is drying out, add a water or broth judiciously.
Optionally, sprinkle the shredded cheese over the spaghetti and bake for another 5 minutes, or until the cheese is melted, golden, and bubbling.
Remove from the oven and garnish with chopped fresh herbs before serving.
