To broil patties, place on broiler pan; broil 4 to 6 inches from heat using times above as a guide, turning once. Meanwhile, place pineapple slices and buns, cut side up, on broiler pan; broil 1 to 2 minutes or until buns are lightly toasted. Turn pineapple slices; broil an additional 1 to 2 minutes.
Liquid smoke gives foods a smoky flavor without adding fat or sodium. Look for it next to the barbecue sauce in the condiment section of the grocery store.
Keep a spray bottle filled with water near the grill to handle flare-ups.
Serve these barbecue burgers with corn on the cob, watermelon cubes and iced tea or lemonade.