Shape the beef mixture into ¾-inch meatballs and arrange them on the baking sheet, then bake for 10 min and, if you want a little color, broil at 475 °F for up to 1 min before setting them aside. Keep them small and spoon-sized so they fit the pasta perfectly, and cook them until they’re no longer pink in the center and reach 160 °F for ground beef as checked with a thermometer, following
the USDA temperature for ground beef meatballs.