Heat olive oil in a skillet over medium-high heat.
2 tbsp. olive oil
Cook the garlic and onion for 1 to 2 minutes.
2 garlic cloves, 1 onion
Add the beef and cook until browned, about 4 to 5 minutes.
1 lb. ground beef
Add in the diced tomatoes, bell pepper, oregano, basil, parsley, and tomato paste.
1 bell pepper, 2 cups tomatoes, 2 tsp. dried oregano, ¼ cup fresh basil, 1 tbsp. fresh parsley, 2 tbsp. tomato paste
Cook everything while stirring for 3 to 4 minutes.
Pour in the tomato sauce, stir everything, and season to taste with salt and pepper to complete the lasagna sauce.
4 cups tomato sauce, Sea salt and freshly ground black pepper
Alternate layers of zucchini and eggplant topped with lasagna sauce in a slow cooker.
2 medium zucchini, 1 medium eggplant
Finish with one last layer of lasagna sauce, top with fresh basil, cover, and cook on low for 4 to 6 hours.