01 -
Combine olive oil, lime juice, minced garlic, ground cumin, smoked paprika, salt, and black pepper in a mixing bowl and whisk until well incorporated.
02 -
Place flank or skirt steak in a resealable bag or shallow dish, pour marinade evenly over the meat, seal or cover, and refrigerate for a minimum of 1 hour, preferably overnight to enhance flavor.
03 -
Preheat a grill or heavy skillet on high heat. Remove steak from marinade, allowing excess to drain, and grill for 5–7 minutes per side until the desired doneness is reached. Rest briefly, then slice the steak thinly across the grain.
04 -
Arrange tostada shells on a serving platter. Distribute sliced carne asada over each shell. Add a generous layer of guacamole, a dollop of sour cream or crema, and top with diced tomatoes, chopped cilantro, and sliced jalapeños if using.
05 -
Present immediately with lime wedges alongside for squeezing over the tostadas.