An ancho chile powder rub gives lots of flavor and a little bit of spice to these simple but delicious burritos. Slideshow: More Steak Recipes
In a small resealable plastic bag combine the steak and the beer; refrigerate for 1 hour.
Remove the steak from the marinade and dry thoroughly with paper towels. Season the steak on both sides with the ancho chile powder, sea salt and ground pepper. In a small nonstick frying pan, heat the oil over medium high heat. Add the steak to the pan and give it a little shake to prevent it from sticking. Sear the steak for 3 to 5 minutes per side. Remove the pan from the heat and let the steak stand, covered, for 10 minutes. Slice it across the grain into 1-inch strips.
In a small bowl, mash together the avocado, lime juice, garlic and sea salt.
In a medium nonstick frying pan over medium high heat, warm the tortillas for 30 seconds each.
Divide the guacamole between the warmed tortillas and top each with half of the steak. Add the sour cream, salsa, halved grape tomatoes and cilantro, if desired, then roll into burritos.