Crockpot Lasagna

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• 1 pound 90% lean ground beef
• 1 each small yellow onion (diced)
• 1 teaspoon dried oregano
• 1 teaspoon kosher salt (divided)
• ½ teaspoon ground black pepper (divided)
• 6 cloves garlic (minced, about 2 tablespoons)
• 1 teaspoon balsamic vinegar
• ¼ teaspoon red pepper flakes (optional)
• 32 ounce good-quality marinara sauce (4 cups, divided)
• 24 ounces low-fat cottage cheese (or part-skim ricotta cheese, about 3 cups)
• 10 ounce or box frozen spinach (thawed and squeezed very dry)
• 1 each large egg
• ⅔ cup grated Parmesan cheese
• ½ cup packed fresh basil leaves (chopped, or ¼ cup chopped fresh parsley, plus additional for serving)
• 9 each dry lasagna noodles (do not use oven ready/no boil noodles)
• 8 ounces part-skim mozzarella cheese (shredded, about 2 cups)
• ¼ cup water

1. Coat a 6- or 7-quart slow cooker very generously on the bottom and sides with nonstick spray. Heat a large, deep pan over medium-high heat. Add the beef, onion, oregano, ½ teaspoon of the salt, and ¼ teaspoon of the pepper. Cook, breaking apart the meat with a spatula or spoon, until the meat is browned and cooked through, about 5 minutes. Add the garlic, balsamic vinegar, and red pepper flakes and cook 30 seconds.
2. Reserve 1 cup of the marinara sauce. Remove the pan from the heat and add the remaining 3 cups marinara sauce. Stir to combine, then set aside.
3. In a large bowl, use a fork to stir together the cottage cheese, spinach, egg, Parmesan, basil, and the remaining ½ teaspoon salt and ¼ teaspoon pepper until evenly combined. Use the fork to break apart the spinach as needed.
4. Assemble the lasagna: spread the reserved 1 cup marinara sauce on the bottom of the slow cooker. Lay 3 of the noodles on top of the sauce, breaking them as needed to make a roughly even layer—it doesn’t need to be perfect and is fine if some of the noodles overlap slightly and parts of the sauce peek through. I typically lay one noodle down the center, then break the other two in half and arrange them in a wide "V" in the open spaces on either side of the center noodle.
5. Top with one-third of the meat sauce, spreading it into an even layer.
6. Evenly dollop half of the cottage cheese mixture over the meat sauce. With the back of a fork, spread it into an even layer.
7. Sprinkle with one-third of the mozzarella.
8. Repeat layers with the next 3 noodles, half of the remaining meat sauce, all of the remaining cottage cheese mixture, and half of the remaining mozzarella.
9. Finish layering with the 3 final noodles and remaining meat sauce (refrigerate the last portion of the mozzarella until the end—if you add it now, it will disappear into the sauce while the lasagna cooks). Gradually pour the water in a slow stream over the top and around the edges of the lasagna, allowing some of it to trickle down the edges so it flows between the lasagna and the insert.
10. Cover the slow cooker and cook on LOW for 3 to 4 hours, until the noodles are tender and the lasagna registers 140 degrees F in the center (do NOT cook on high or the noodles will not cook through evenly— mine was done in 3 hours and 15 minutes). Turn off the slow cooker, uncover, and sprinkle with the remaining mozzarella.
11. Carefully remove the insert from the base and set it on a wire rack (use oven mitts if needed; the insert is hot). Recover and let the lasagna rest for at least 20 minutes (if you serve it right away, it will fall apart). To serve, sprinkle the top generously with more fresh basil. Cut the lasagna with a knife and scoop out servings with a big spatula or spoon. Enjoy hot.