First, a few notes: To achieve medium-rare results (125 degrees before resting), grill meat quickly on high heat (see times below). Before slicing, be sure to let the cuts rest (typically for 10 minutes, although thicker cuts may need longer and vice versa for smaller pieces). Finally, pair the cuts with a spicy butter (try this spicy, savory Sriracha butter) or salsa for added flavor. And remember, for four people, one pound of meat should do.
Sirloin: Flavorful, well priced, and generally the most tender of these four. Cook a ½- to ¾-inch-thick steak three minutes per side.
Skirt: This long steak is thicker on one end; for easy handling and even cooking, cut it into several pieces before grilling. Cook a ¼- to ½-inch-thick steak two to four minutes per side.
Hanger: This less-familiar cut has the boldest flavor of the bunch. Cook a 1- to 1½-inch-thick steak six to seven minutes per side.
Flank: aka London broil, this has a mild flavor. Cook a ¾- to 1-inch-thick steak five to six minutes per side.