Heat olive oil in a large skillet over medium-high heat. Add the corn and cook, stirring frequently, until it starts to char and develop color, about 5-7 minutes. Remove from heat and let cool.

In a large bowl, combine mayonnaise, lime juice, lime zest, minced garlic, Tajin, chili powder, and salt. Mix well to create a sauce. Add the cooled corn, cilantro, scallions, diced jalapeño, and cotija cheese to the bowl. Stir until everything is well combined. Top with extra cotija cheese, Tajin, and chili powder if desired.

In a food processor or blender, purée cilantro leaves with pickled jalapeños and 2 tablespoons of their juice until finely minced, scraping down the sides as needed. In a mixing bowl, combine mayonnaise, sour cream, ranch seasoning, garlic powder, and salt. Mix until smooth. Stir in the cilantro mixture and lime juice. If you prefer a thinner consistency, add buttermilk a splash at a time until desired thickness is reached.

Divide the ground beef into 3.5-ounce portions. Press each portion into a 6-inch flour tortilla, creating a thin, even layer that slightly overlaps the edges. Season with salt and pepper. Heat a griddle or large skillet over high heat. Place the tortillas burger-side down and press firmly with a spatula or burger press. Cook undisturbed for 2-3 minutes. Carefully scrape underneath the burgers with a spatula, flip the tortillas, and cook for an additional 1-2 minutes until cooked through.

Assemble your tacos by adding the creamy jalapeno sauce on top of the smash burgers and serve with the street corn on the side.