I used Narwhal Russian Imperial Stout which was amazing. But you can use whatever stout beer you like.
Stout Skirt Steak
2 1 1/3-Pound Flank Steaks
1 Tony Chachere Creole Seasoning
1/4 Cup Extra-Virgin Olive Oil
1 12-Ounce Bottle Stout
1/2 Cup Worcestershire Sauce
Place steaks in container large enough to hold the steaks. It's okay if you have to fold them over.
Drizzle the meat with olive oil and make sure they're coated evenly. Sprinkle steaks on both sides with Chachere Creole Seasoning. Add beer and Worcestershire sauce, turning steaks several times to coat both sides.
Cover and chill at least 3 hours or up to a day ahead, turn occasionally.
Remove from the refrigerator about 30 minutes before your going to cook them to bring up the temperature. They will be more tender if they are at a warmer temperature than if you cook them straight from the fridge.
Preheat your grill to medium-high. Grill steaks to desired doneness, 3 to 4 minutes total per side for medium-rare
Transfer steaks to cutting board; let rest 5 minutes. Thinly slice steaks across grain.
Serve as a main dish with your favorite sides or on a sub roll with beer glazed onions or serve on homemade beer tortillas, with aji Sauce, guacamole and shredded cheese.