Cut squash in half and lay face down on a greased cookie sheet. Bake 30-35 minutes or until squash is tender. Scrape with fork to remove squash in strands. Hint: Wrap in paper towels and refrigerate for a few hours or overnight to absorb excess moisture.
Stir diced tomatoes and jarred sauce together in saucepan and heat on stove.
Cook ground sausage in a skillet on medium-high heat until browned. Add peppers; sauté for a few minutes, then add onion and garlic. Sauté for a few more minutes. Drain grease, if needed.
In separate bowl, mix 2 cups cottage cheese with 1 cup shredded cheese. Set aside.
In large bowl, mix together squash, pasta sauce and tomatoes. Set aside.
In greased 13x9x2-inch baking dish, spread 1/3 of the squash mixture evenly. By layers, add half cheese mixture, half sausage, a third of the squash mix, remaining cheese mixture, remaining sausage and the remaining squash. Spread 1 1/2 cups of sauce over the top. Add 1 cup of Italian cheese blend over sauce. Top with Italian seasoning.
Bake at 350 degrees for 30 minutes. Let rest 15 minutes before serving.