Cook macaroni according to package directions. Meanwhile, place cottage cheese in a food processor; cover and process until smooth. Set aside.
In a large saucepan, melt butter. Stir in the flour, salt, pepper and garlic salt until smooth. Gradually add cream and milk. Bring to a boil; cook and stir for 2 minutes or until thickened.
Drain macaroni; transfer to a large bowl. Add the cheddar cheese, cottage cheese and white sauce; toss to coat. Transfer to a greased 13-in. x 9-in. baking dish. (Dish will be full.) Combine bread crumbs and butter; sprinkle over the top.
Bake, uncovered, at 400° for 20-25 minutes or until bubbly.