Whisk lime juice, olive oil, garlic, chili powder, cumin, oregano, paprika, salt, and pepper.
Pat steak dry. Coat with the marinade in a bowl or bag. Chill 15–20 minutes.
Heat a large skillet over medium-high. Add the neutral oil until shimmering.
Sear the steak 3–4 minutes per side until nicely browned and medium-rare.
Rest the steak 5 minutes. Slice thinly against the grain.
Warm tortillas in a dry pan or over a flame until pliable.
Assemble tacos with steak, onion, cilantro, avocado, salsa, cotija, and jalapeño.
Serve immediately with extra lime and hot sauce, if desired.