For the steaks:
- 4 small flatiron steaks (6-7 ounces each) or 1 1/2 to 1 3/4 pound flank steak, at room temperature
- Vegetable oil, for coating
- 2 teaspoons ancho (mild) or chipotle (hot) chili powder
- 1 teaspoon Montreal steak seasoning or salt and pepper
For the sauce:
- 1 large or 2 small ripe avocados, flesh scooped from the skin
- Juice of 2 limes
- 1 large clove garlic, peeled
- 1 jalapeño chili pepper, seeded and coarsely chopped
- 2 tomatillos, peeled and coarsely chopped
- 1/2 small red onion, coarsely chopped
- 2 teaspoons honey or a sprinkle sugar
- A generous sprinkle of sea salt
- A small handful of cilantro leaves
- A small handful of fresh mint leaves
- A few sprigs of thyme
For the tacos:
- 8 flour tortillas (8-inch)
- All-natural cooking spray
Pre-heat an outdoor grill or grill pan to medium-high. Rub the steaks with oil, chili powder and steak seasoning. Grill the steaks, tented loosely with foil, turning once, for 15 minutes for medium-rare doneness. Remove from the heat and let rest.
Combine the sauce ingredients in a blender or food processor and puree until almost smooth.
Lightly spray the tortillas with cooking spray and char for a few seconds on each side on the grill or stovetop.
To form each slider, spread some sauce on each tortilla, top with very thinly sliced steak in an even layer and fold the tortilla into quarters.