Lasagna without greens

1 tablespoon olive oil 1 small onion , chopped 1/2 cup chopped celery 1/2 cup chopped carrot 3 garlic cloves , minced 2 (14 1/2 ounce) cans chopped tomatoes 4[...]

cooking spray (1 spray) 1/2 cup onion , diced 2 cups button mushrooms or 2 cups cremini mushrooms , sliced 2 medium garlic cloves , minced 16 ounces frozen[...]

1/3 cup olive oil 3 large yellow onions , diced (about 3 cups) 3 (28 ounce) cans plum tomatoes , drained 1 tablespoon kosher salt 1 teaspoon fresh ground[...]

2 1/2 cups tomato sauce (homemade or in a jar) salt 3/4 lb spinach leaves, stems removed 8 lasagna noodles, half spinach lasagna if available 1 1/2 cups[...]