Simplify the following text for a Grade 7 native English-speaking person.
Original: Canned spaghetti , kits for making spaghetti , and spaghetti with meatballs became popular , and the dish has become a staple in the U.S.
Simplified: In the United States , there is a kind of spaghetti called `` Alvaro 's spaghetti '' which is served with alfredo sauce . In some countries , like United States or Canada , meatballs are often in the spaghetti sauce .