1. Start by marinating the steak. In a small bowl, mix olive oil, chili powder, cumin, salt, and pepper. Rub this mixture onto the steak, ensuring it is well-coated. Let it sit for at least 30 minutes to allow the flavors to infuse.
2. While the steak is marinating, preheat your grill to medium-high heat. Place the corn directly on the grill, turning occasionally until charred and tender, about 10-15 minutes. Once done, remove from grill and let cool slightly.
3. Next, grill the steak for 6-7 minutes per side for medium-rare, or adjust the time to your preferred doneness. Remove the steak from the grill and let it rest for 5 minutes before slicing thinly against the grain.
4. In a bowl, mix mayonnaise, sour cream, lime juice, and half of the chopped cilantro. Cut the kernels off the cooled corn and mix them into this creamy elote sauce along with the cotija cheese.
5. Warm the corn tortillas on the grill for about 30 seconds per side, just enough to make them pliable.
6. To assemble the tacos, place slices of steak on each tortilla, top with a generous spoonful of the elote mixture, and garnish with additional cilantro and lime wedges for squeezing.

A trick I learned from my abuela: always let the steak rest before slicing to lock in its juices, ensuring each bite is as flavorful as the last.