I found this recipe at Bon Appétit and followed it except that I added red onion. The salsa verde is like a chimichurri, an Argentine sauce. I used cilantro, mint and tarragon, but you can use a different combination of fresh herbs if you like. I was afraid my kids wouldn't like the "green stuff", but they liked it. It gives fresh flavor to a simple steak, whatever cut you would like to use.
Grilled Skirt Steak with Herb Salsa Verde
1/2 c. olive oil, divided
4 garlic cloves, finely chopped
1 T. finely grated lemon zest
Kosher salt and freshly ground black pepper
2 c. coarsely chopped fresh herbs, such as tarragon, savory, and mint
1 c. coarsely chopped flat-leaf parsley leaves
1 skirt steak (about 1 1/2 pounds), trimmed, cut into two or three 10-inch pieces
Mix 1/4 cup oil, garlic, and lemon zest in a medium bowl; season with salt and pepper. Let marinate for 20 minutes. Add all herbs to oil mixture; stir until well coated. Let stand until herbs begin to wilt, about 10 minutes. Stir in remaining 1/4 cup oil. Season herb salsa verde to taste with salt and pepper.
Turn grill on. Season skirt steak generously with salt and pepper and grill until charred, 2 minutes per side for medium-rare. Transfer steak to a serving platter; let rest for 5 minutes, allowing juices to accumulate on platter.
Transfer skirt steak to a cutting board and slice against the grain on a diagonal. Season to taste with salt; return to platter with juices. Spoon half of herb salsa verde over. Serve with lemon wedges. Serve remaining herb salsa verde on the side.