2 cups sour cream
2 tablespoons lime juice plus 1 lime, cut into wedges, for garnish
1 teaspoon ground cumin
12 ounces skirt steak, sliced into 1/2-inch-wide strips
2 cups diced red bell pepper
1/2 cup corn kernels
Kosher salt and freshly cracked black pepper
2 cups fresh cilantro leaves
1 cup very thinly sliced Spanish onions
Six 6-inch white flour tortillas
1 jalapeno, seeded and julienned
1 cup grated cotija cheese