Prepare the street taco seasoning by combining all ingredients in a small bowl. Stir to combine and set aside.

Place the top oven rack in the second position from top and pre-heat broiler to “High.” Line a large, rimmed baking sheet with aluminum foil and set it aside.

Place a large 12” cast-iron skillet over medium-high heat.

Whisk together the sour cream, mayonnaise, and one tablespoon taco seasoning together in a medium bowl and set aside.

Place the flank steak on the prepared baking sheet and evenly brush the olive oil over both sides. Evenly sprinkle one tablespoon taco seasoning over the steak. Generously season with sea salt before turning. Repeat on the other side with the remaining taco seasoning and a little more salt.

Place steak under the broiler for 5-7 minutes, turning once halfway through, or until it reaches the desired level of doneness.

While the steak is broiling, add two corn tortillas to the hot skillet. Heat until they are warmed through and develop a bit of color, approximately 30 seconds to one minute. Flip with tongs and repeat on the remaining side. Transfer the warmed tortillas to a large sheet of aluminum foil (or a tortilla warmer, if you have one).

Repeat Step 7 with the remaining tortillas. To keep warm tortillas, wrap them up in aluminum foil or your tortilla warmer while working on the rest.

When ready, remove the steak from the oven and let rest for 5 minutes before cutting against the grain into thin slices. Transfer the steak to a medium bowl and toss with the fresh lime juice. Set aside.

To serve, layer two warm corn tortillas together, as shown, and add some of the seasoned steak and your choice of toppings, such as sliced radishes, crumbled Cojita cheese, diced avocado, or fresh cilantro.