Preheat oven to 375 degrees F. In a large sauce pan, brown the sausage over medium heat, breaking into small pieces with a wooden spoon. Once the meat is fully cooked, add the marinara and simmer for 10 minutes.
Boil the noodles in a large pot of salty water, according to package instructions. Remove the noodles and lay them out on a clean dish towel.
Spray an 9x13-inch baking dish with non-stick spray. Smear 9-12 noodles with an equal portion of cream cheese. (The number of noodles used depends on the width of the pan.)
Start assembling the lasagna: One large scoop of meat sauce on the bottom, 3-4 noodles across (cream cheese side up), 1/3 of the mozzarella and parmesan. Repeat. After the third layer of noodles with cream cheese, pour the rest of the sauce over the noodles before adding the last layer of the mozzarella and parmesan. Sprinkle the top with Italian Seasoning.
Bake uncovered for 20-30 minutes—until the cheese is toasty and the sides are bubbling. Wait at least 10 minutes before cutting. Lasagna (as well as many other favorite pasta dishes) is considered better the second day. If making this ahead, Cover well, refrigerate, and bake for 40-50 minutes to heat through!