Zucchini and Onion Gratin

Ingredients

• 2 tablespoons olive oil, divided
• 1 large onion, quartered lengthwise and thinly sliced
• 1 tablespoon tomato paste
• 2 teaspoons grated lemon rind
• 1 teaspoon fresh thyme leaves
• 3/8 teaspoon kosher salt, divided
• 1/4 teaspoon freshly ground black pepper
• 1 1/2 pounds zucchini, diagonally sliced into 1/4-inch-thick pieces
• 1 ounce Parmesan cheese, grated (about 1/4 cup)

Directions

Heat a large skillet over medium heat. Add 1 tablespoon oil to pan; swirl to coat. Add onion; cook 6 minutes, stirring occasionally. Stir in tomato paste; cook 2 minutes. Stir in rind, thyme, 1/8 teaspoon salt, and pepper; cook 2 minutes, stirring occasionally.
Preheat broiler to high.
Arrange zucchini on a jelly-roll pan. Drizzle with remaining 1 tablespoon oil; toss. Broil 7 minutes or until lightly charred. Sprinkle with remaining 1/4 teaspoon salt.
Preheat oven to 375°.
Spread onion mixture in a 2-quart gratin dish. Arrange zucchini mixture over onion mixture. Sprinkle with cheese. Cover and bake at 375° for 25 minutes. Remove from oven.
Preheat broiler to high.
Uncover zucchini mixture; broil 1 1/2 minutes or until lightly browned.

Makes 6 servings
Serving Size: 1 cup

Nutrition

Adapted from: EatingWell.com and CookingLight.com