1. Cut steak into 1 1/2-inch pieces and season with 1 1/2 teaspoons salt. Chill in a sealable bag 4 to 6 hours.
2. Rinse steak under cold water, then pat dry. Grind the steak using a meat grinder with a 3/8-inch or 1/4-inch die. Grind the steak a second time. Combine the meat with the garlic and paprika and form into 4 (4-inch) patties.
3. Stir together the chipotle and mayonnaise in a small bowl.
3. Preheat a grill with a medium-high heat. Grill the burgers, covered, turning once, 4 to 6 minutes for medium. (Burgers will continue to cook slightly once removed from grill.)
4. Put burgers on rolls and top with chipotle mayonnaise, queso fresco, cilantro, and avocado slices.