Stuffed Zucchini Boats with Beef and Mozzarella - Quickie Recipe

Ingredients

• 4 medium zucchini, about 2 lb (900 g) total
• 1 tablespoon olive oil, divided
• 1/2 teaspoon kosher salt, divided
• 1/4 teaspoon black pepper
• 1 lb (450 g) lean ground beef
• 1 small yellow onion, finely chopped
• 1 cup (120 g) chopped scooped zucchini flesh
• 3 cloves garlic, minced
• 1 1/2 cups (360 ml) marinara sauce
• 1 teaspoon Italian seasoning
• 1/4 teaspoon red pepper flakes, optional
• 1 cup (115 g) shredded mozzarella cheese
• 1/4 cup (25 g) grated parmesan cheese
• 2 tablespoons chopped fresh parsley or basil