In a large frying pan, brown ground beef and Italian sausages. Break up the meat into smaller pieces as it cooks. Add onions and salute with 2 cloves of minced garlic.
Drain excess oil off of the frying pan.
Add tomato sauce to the meat mixture. Cut an onion in half, and add this to the sauce. The onion will release its flavors into the sauce, making it very tasty.
Add Italian seasoning, salt and pepper, carrots, celery and mix into the sauce. Set the temperature to low and let simmer for 30 minutes.
At the end of cooking the meat sauce in the last minute, add the strips of fresh basil to the sauce.
Remove the meat sauce from the heat source and set aside.
If you are using fresh spinach, cook it in a large frying pan over medium heat until it has wilted down. It should take about 10 minutes. Remove all water from the spinach by squishing it when it has cooled down. Use a paper towel around the spinach to draw out more water from the spinach. If you are thawing spinach from frozen, place it in the microwave for 30 second intervals until it has fully thawed. Remove the water from the spinach.
In a medium bowl, combine ricotta, egg, 1/4 cup mozzarella cheese, 1/4 cup parmesan cheese, spinach, and 1 tsp Italian seasoning. Mix together until fully combined.
In a 9 x 13 baking pan or casserole dish that has high sides, place meat sauce on the bottom of the pan until it's fully covered (about half of the meat sauce). Add lasagna noodles lengthwise to the baking pan. Make adjustments as needed by breaking apart the noodles to fully cover the meat sauce.
Add the next layer on top of the meat sauce/lasagna noddle's by adding 1/2 of the ricotta mixture. Spread the ricotta mixture so it's one layer that goes right to the edges. Add another layer of lasagna noodles.
Add the rest of the meat sauce on top of the last layer of lasagna noodles. Add another layer of lasagna noodles.
Add the rest of the ricotta mixture and spread evenly. Add a layer of lasagna noodles.
Add 3/4 cup mozzarella cheese and 1/2 cup parmesan cheese to the top of the lasagna. Fully cover the lasagna noodles in cheese. If you don't, the noodles will end up dry and you won't want to eat them.
Bake at 350 degrees F for 35 minutes. Then, broil for 3-5 minutes to brown the cheese to your liking.
Let the lasagna sit for 10 minutes before cutting into. It will be very hot, and needs to cool down before eating.
Lasagna is good for up to 3 days in the refrigerator.