In a bowl, combine olive oil, lime juice, minced garlic, cumin, chili powder, salt, and black pepper. Add the flank steak, ensuring it's well coated. Cover and marinate in the refrigerator for at least 1 hour or overnight for best results.

Grill the Steak

Preheat a grill or grill pan over medium-high heat. Remove the steak from the marinade and grill for about 5-7 minutes on each side, or until it reaches your desired level of doneness. Remove from heat and let it rest for 5 minutes.

Slice the Steak

Thinly slice the grilled steak against the grain. This will ensure tenderness in each bite.

Warm the Tortillas

In a dry skillet over medium heat, warm the corn tortillas for about 30 seconds on each side until pliable.

Assemble the Tacos

To each tortilla, add slices of carne asada, then top with chopped cilantro, diced onion, sliced radishes, a dollop of sour cream, and a spoonful of salsa.

Serve

Serve the tacos immediately while warm, garnished with additional lime wedges if desired.