1/3 cup (50 grams) finely grated Parmigiano-Reggiano cheese
Heat broiler to high and position a rack 15 centimeters from broiler.
Heat butter in a large non-stick oven-safe pan over medium heat. Add panko and chili flakes and cook for two to three minutes, stirring occasionally until panko is lightly toasted. Season with salt and pepper and set aside in a small bowl.
Score the cut side of zucchinis with a cross hatch pattern and drizzle with olive oil. Season with salt and pepper. Increase heat to medium-high and cook zucchini in pan, cut-side down, for three to five minutes until golden. Remove from heat.
Stir cheese into panko mixture. Top scored side of zucchinis with panko mixture. Place in oven and broil until browned, checking often, between two to four minutes.