1. Build charcoal fire or preheat gas grill for direct cooking. Mix ground sirloin and chuck together gently with salt and pepper. Form into 6 patties. Press indentation in center of each patty (see "shaping the burgers," below). Brush with olive oil. Place directly over medium heat (about 400 degrees F); grill 10 to 12 minutes, turning once halfway through. Remove from grill. Top with a tablespoonful of Pimiento Cheese. Serve on buns.
Hanger Steak Burger:Cut about 2 lbs. cold hanger steak in 1-inch pieces. put through a meat grinder or place 1/4 at a time in food processor; pulse until finely ground. Season, shape into patties, and grill as above. Makes 6 servings.
Pimiento Cheese: Grate shallot on a box grater or process in a food processor. Mix shallot and cheese. Add mayo and stir with a large fork just until mixture holds together. Stir in pimientos and some of their liquid. Season with pepper. Refrigerate, covered, until ready to use. Store, refrigerated, up to a week.
Shaping the burgers:Both Elizabeth and Jamie press an indentation in the patties so that they don't puff up in the center as they cook. Gently form patties, then press down slightly in the center to form an indentation about an inch wide.
Direct Grilling:For this method, the food is placed on the grill rack directly over the heat source. Direct grilling is best for searing and cooking small, tender cuts that cook in 30 minutes or less, such as steaks, burgers, or boneless chicken.