Dice half of the onion finely, leaving the other half as a piece. Put the canned tomatoes in a large saucepan, add the butter, half onion piece as well as the finely diced onion, grated carrot, optional veggies, and salt. Cook, covered, at a slow simmer for about 45 minutes. Cooking it covered helps retain the moisture to soften the diced onion. Check to see if softened enough to fool the grandkids. Can cook longer if needed.
After 45 minutes remove the onion piece and set aside, or give to hubby to eat right away and hide the evidence. Use a stick blender to puree the sauce. Option: leave a few chunks of tomato to confirm (fool the grandkids) that it is a TOMATO sauce.
Spoon over cooked pasta and top with parmesan cheese, if possible, depending on which grandkid likes it.
Cut up 2 mild Italian sausages into ½ inch pieces. Cook them in a frying pan until done and pretend they are meat balls.