Preheat the oven to 350°.
In a large pot, boil the manicotti for the lowest time indicated on the package. Drain and pour cold water over the manicotti to stop the cooking and keep them from sticking.
Meanwhile, in a skillet, cook the ground beef and sausage. Crumble the meats and continue cooking until they are no longer pink. Drain. Add the garlic and cook and stir for 1 more minute. Add spaghetti sauce.
In a medium bowl, combine cottage cheese, 1 cup mozzarella, ¼ cup parmesan, egg, parsley, onion powder, pepper, and garlic powder.
To assemble the manicotti, start by scooping one cup of the meat sauce into the bottom of a greased 9x13 baking dish. Stuff the shells with the cottage cheese mixture using your hands. Lay the stuffed shells in the baking dish. (If a shell breaks, don't worry; just reform it into the correct shape and place it in the baking dish.) Top the stuffed manicotti shells with the meat sauce. Then sprinkle with the remaining mozzarella and parmesan.
Bake the manicotti for 35-40 minutes until heated through. Cover with greased foil if the cheese starts to get too brown.