Pasta Moussaka

Ingredients

• Cooking spray or butter, for baking dish -
• 1 lb. ziti -
• 1/4 c. freshly grated Parmesan -
• 1/4 c. extra-virgin olive oil -
• 1 medium yellow onion, chopped -
• 1 lb. lean ground beef (90% or above) -
• 4 cloves garlic, minced -
• 1 tsp. ground cinnamon -
• 1 tsp. paprika -
• 2 tsp. dried oregano -
• 1 bay leaf -
• 2 (28-oz. cans) diced tomatoes -
• Kosher salt -
• 1 tsp. sugar -
• 2 medium eggplants, cut into 1" chunks  -
• 1/2 c. dry red wine -
• Freshly ground black pepper -
• 2 c. whole milk -
• 4 tbsp. butter -
• 1/3 c. all-purpose flour -
• Pinch freshly grated nutmeg -
• 2 egg yolks -