Prepare the chimichurri by combining the cilantro, parsley, garlic, jalapeño, red wine vinegar, lime juice, kosher salt, black pepper, and crushed red pepper flakes in a food processor. Pulse until finely chopped. With the processor running, slowly drizzle in the extra virgin olive oil until combined but still slightly textured. Set aside.

Pat the steak dry with paper towels. Rub with 1 tablespoon of the extra virgin olive oil, then season evenly with the kosher salt, chili powder, cumin, smoked paprika, and black pepper, pressing the spices into the meat. Toss with 1/4 cup chimichurri and let sit for at least 15-20 minutes.

Heat a large cast iron skillet or grill pan set over medium-high heat. Alternately, use a gas grill set to medium-high heat. Cook the steak for 4-5 minutes per side for medium-rare, or until cooked to your preferred doneness. Transfer to a cutting board and rest for 5-10 minutes.

Heat the remaining 1 tablespoon extra virgin olive oil in a large skillet set over medium heat. Add the poblano pepper and yellow onion. Cook for 8-10 minutes, stirring occasionally, until softened and lightly caramelized.

While the steak rests, warm the tortillas in a dry skillet or the microwave for several seconds until soft. Keep wrapped in a clean kitchen towel.

Slice the steak thinly against the grain. Toss several spoonfuls of the chimichurri with the sliced steak.

Fill each tortilla with sliced steak, sautéed poblano peppers and onions, avocado, pickled red onions if using, and cotija cheese. Spoon additional chimichurri over the tacos and serve with lime wedges.