Sausage Pasta with Spinach and Mushrooms

Name: Sausage Pasta with Spinach and Mushrooms
Prep time: 5 min
Cook time: 20 min
Total time: 25 min
Cuisine: Mediterranean
Ingredients: 6 mild Italian sausages; 2 tbsp olive oil (extra virgin); 16 oz fusilli pasta (usually 1 box); 4 quarts water; 1 tbsp salt (this is for pasta water); 1 white onion; 4 garlic cloves (add more to taste); 1 red bell pepper; 2 cups sliced white mushrooms; 8 oz tomato sauce; salt / pepper to taste; 1 tsp oregano; 0.5 tsp paprika; 0.5 tsp crushed red pepper (add more for a spicier dish); 2 cups spinach (you can use baby spinach too); 1 tbsp freshl, chopped Italian parsley; freshly grated parmesan cheese (add to taste, usually 2 tbsps per adults but my kids eat less)