Weeknight Harissa Eggplant Parm

Name: Weeknight Harissa Eggplant Parm
Ingredients: 5 Tbsp. plus ⅓ cup extra-virgin olive oil, divided; 1 cup panko; 2 tsp. Diamond Crystal or 1 tsp. Morton kosher salt, divided, plus more; 1 lb. globe eggplant (about 1 medium), cut into 1 pieces; 1 medium onion, finely chopped; 5 garlic cloves, thinly sliced; ¼ cup harissa; ¼ tsp. crushed red pepper flakes (optional); 1 28-oz. can crushed tomatoes; 12 oz. fresh mozzarella, coarsely grated (about 1½ cups); 2 oz. Parmesan, finely grated (about 1 cup); Parsley leaves with tender stems and basil leaves (for serving)