Roasted Eggplant Moussaka with Lamb

Name: Roasted Eggplant Moussaka with Lamb
Ingredients: 3 medium (1-pounds) eggplants, sliced into 1/2-inch-thick rounds; 6 tablespoons extra-virgin olive oil, divided; 2 ¾ teaspoons kosher salt, divided; 1 pound ground lamb; 1 (3-inch) cinnamon stick; 4 medium garlic cloves, minced; 1 tablespoons tomato paste; 2 teaspoons dried oregano; ¼ teaspoon crushed red pepper; ½ cup (4 ounces) dry red wine; 1 (14.5-ounce) can crushed tomatoes; 1 ½ cups whole-milk ricotta cheese; 2 ounces low-moisture part-skim mozzarella cheese, shredded (about 1/2 cup); 1 large egg; 2 ounces Parmesan cheese, grated (about 1/2 cup)