In a large pot, heat olive oil over medium heat and sauté onions and garlic for 5 minutes, add the next 7 ingredients (eggplant through salt and pepper) and simmer for 25
minutes.
In a large blender or food processor, blend sauce 1 to 2 minutes until smooth. Return to pot, stir in ricotta cheese and cook over medium heat 1 to minutes until warm.
Toss pasta with sauce and top with Parmigiano-Reggiano cheese.