Cheesy Baked Ravioli and Romaine Salad

Preheat oven to 375°F. Heat 2 tablespoons oil in a large skillet over medium. Add onion; cook, stirring often, until tender, about 5 minutes. Add tomato paste and Italian seasoning; cook, stirring constantly, for 1 minute. Add crushed tomatoes and ½ teaspoon each salt and pepper. Bring mixture to a simmer over medium; cook, stirring occasionally, until sauce is thickened, about 10 minutes. Remove from heat.

Grease a 13-by-9-inch or other 3-quart baking dish with 1 tablespoon oil. Spread 1 cup tomato sauce in bottom of dish.

Arrange half of ravioli over sauce in baking dish in a single layer, slightly overlapping ravioli. Spread 1 cup tomato sauce evenly over ravioli. Sprinkle with half of cheese. Repeat layers once, using remaining ravioli, tomato sauce, and cheese. Bake until sauce is bubbly and cheese is melted and golden, 30 to 35 minutes.

Whisk lemon zest, lemon, juice, and remaining ½ cup oil, ¾ teaspoon salt, and ½ teaspoon pepper in a large bowl until combined. Add lettuce and gently toss to coat. Serve salad alongside baked ravioli.