Spaghetti sauce with hidden extras

I am an Australian mother to 6 kids. One of our family favorites for dinner is spaghetti bolognaise. I cook it in bulk (10lbs of ground beef), add lots of pureed tomatoes, onions (finely diced), garlic and oregano and then stretch it with about 2lbs red lentils and 3lbs grated carrots. The lentils and carrots turn into mush as you cook it and the kids don't even know they are eating 'health food'. I freeze it in family sized portions so that when we are busy I just need to cook the pasta while the sauce defrosts in the microwave. Serve with grated cheese.