Step 1: Sauté the Aromatics
In a large pot or Dutch oven, heat the olive oil over medium heat. Add the diced onion and cook until softened, about 3-4 minutes. Add the minced garlic and cook for another 1 minute.
Step 2: Build the Soup
Pour in the crushed tomatoes and broth. Stir in the oregano, basil, red pepper flakes (if using), salt, and pepper. Bring to a boil, then reduce the heat to medium-low and simmer for 10 minutes.
Step 3: Add the Ravioli and Spinach
Add the ravioli and cook according to package instructions, about 5-7 minutes. Stir in the fresh spinach and cook until wilted, about 2 minutes.
Step 4: Garnish & Serve
Ladle the soup into bowls and garnish with grated Parmesan cheese and fresh basil. Serve hot with crusty bread on the side.