Hamburgers with Mustard and Mixed Herbs

 

2
pounds lean ground beef
1/2
cup finely chopped red onion
1/3
cup chopped fresh basil
1/4
cup chopped fresh parsley
2
tablespoons chopped fresh thyme
2
tablespoons Worcestershire sauce
2
tablespoons Dijon mustard
8
1/2-to 3/4-inch thick red onion slices
2
tablespoons olive oil
8
hamburger buns, split, toasted
8
lettuce leaves
8
tomato slices

 

 

Gently mix first 7 ingredients in medium bowl until just blended.  Shape into eight 1/2-to 3/4-inch-thick patties.  Can be made 8 hours ahead.  Cover and refrigerate.

 

Prepare barbecue (medium-high heat).  Brush onion slices with oil.  Sprinkle patties and onions with salt and pepper.  Grill to desired doneness, about 5 minutes per side for medium; grill onions until tender, about 5 minutes per side.

 

Place patties on bottom halves of buns.  Top with grilled onions, lettuce, tomato and top halves of buns.