- 2 10-ounce packages chopped frozen spinach, thawed and squeezed to remove excess moisture
- 1 cup ricotta
- 3/4 cup grated Parmesan (3 ounces)
- 3 cups marinara sauce
- 6 regular lasagna noodles (not no-boil)
- 1 1/2 cups grated mozzarella (6 ounces)
- 2 tablespoons olive oil
- 2 teaspoons red wine vinegar
- kosher salt and black pepper
- 1 small head romaine lettuce, cut into strips (about 8 cups)
- 1 cucumber, thinly sliced
- 1/2 small red onion, thinly sliced
- In a bowl, mix together the spinach, ricotta, and ½ cup of the Parmesan. In a second bowl, mix together the marinara sauce and ½ cup water.
- Spread ¾ cup of the marinara mixture in the bottom of a 4- to 6-quart slow cooker. Top with 2 noodles (breaking to fit), ¾ cup of the remaining marinara mixture, half the spinach mixture, and ½ cup of the mozzarella; repeat. Top with the remaining noodles, marinara mixture, mozzarella, and Parmesan.
- Cover and cook on low until the noodles are tender, 3 ½ to 4 hours.
- In a large bowl, whisk together the oil, vinegar, ½ teaspoon salt, and ¼ teaspoon pepper. Add the lettuce, cucumber, and onion and toss to combine. Serve with the lasagna.