Grilled Steak Burritos with Avocado Pico de Gallo

In a glass baking dish, rub steak with cumin, 1 garlic clove, 2 tablespoons lime juice, and 1 tablespoon olive oil. Heat 1 tablespoon olive oil in a small saucepan. Add 1 clove garlic and sauté until fragrant, 1 minute. Add black beans and sauté until thickened, 4 to 5 minutes. Season with salt and pepper and stir in 2 tablespoons lime juice. In a medium-sized bowl, stir together tomatoes, red onion, 3 tablespoons cilantro, 2 tablespoons lime juice, and 1 tablespoon olive oil. Stir in avocado and season with salt and pepper. Heat a grill pan over high heat. Season steak with salt and pepper and grill 2 to 3 minutes per side, or until desired doneness. Let sit 5 minutes, then slice thinly on the diagonal. In a small bowl, stir together rice and 2 tablespoons cilantro and season with salt and pepper. Rub a large nonstick skillet with remaining 1 tablespoon olive oil. Add tortillas and crisp, 30 seconds per side. In the center of each tortilla, place small mound of rice, then beans, avocado, pico de gallo, several slices of steak, lettuce, and, if desired, a sprinkling of cheese and a dollop of sour cream. Carefully roll tortilla around filling, pulling in sides as you roll. Return burritos to skillet to crisp slightly, 30 seconds more per side. Halve each burrito in half and serve immediately.