Zucchini Casserole with Parmesan

Ingredients (9)

• 8 cups sliced zucchini
• 3 tablespoons butter
• 1 teaspoon kosher salt
• 1/4 teaspoon freshly ground black pepper
• 1/3 cup sour cream
• 1 large egg yolk
• 1/2 cup grated Parmesan cheese
• 2 tablespoons chives
• 1/4 cup dried bread crumbs