Step 1

Place a rack in upper third of oven; heat broiler. Heat 3 Tbsp. extra-virgin olive oil in a large ovenproof skillet over medium-high. Add 1 cup panko and 1 tsp. Diamond Crystal or ½ tsp. Morton kosher salt. Cook, stirring often, until panko is golden brown and crisp, about 3 minutes. Transfer to a small bowl.

Step 2

Heat ⅓ cup extra-virgin olive oil in same skillet over medium. Add 1 lb. globe eggplant (about 1 medium), cut into 1″ pieces, and cook, tossing occasionally, until lightly browned, about 5 minutes. Sprinkle in 1 tsp. Diamond Crystal or ½ tsp. Morton kosher salt and cook, stirring often, until eggplant is well browned and tender, 5–7 minutes. Transfer to a medium bowl.

Step 3

Heat remaining 2 Tbsp. extra-virgin olive oil in same skillet over medium. Add 1 medium onion, finely chopped, and cook, stirring often, until softened, about 4 minutes. Add 5 garlic cloves, thinly sliced, and cook, stirring often, until fragrant, about 2 minutes. Add ¼ cup harissa and ¼ tsp. crushed red pepper flakes (if using) and cook, stirring often, until slightly darkened in color, about 2 minutes. Add one 28-oz. can crushed tomatoes and cook, stirring often, until sauce is slightly thickened, 5–7 minutes; season with salt.

Step 4

Add eggplant back to pan and stir into sauce. Sprinkle panko evenly over and scatter 12 oz. fresh mozzarella, coarsely grated (about 1½ cups), and 2 oz. Parmesan, finely grated (about 1 cup), on top (cheese should completely cover panko).

Step 5

Broil eggplant parm until cheese is melted and blistered, about 3 minutes. Remove from broiler and top with parsley leaves with tender stems and basil leaves just before serving.