Heat a grill to medium-high (375 degrees F) or a grill pan to medium-high heat.
In a small bowl, combine the paprika, cumin, garlic powder, chili powder, sea salt, dried oregano, and black pepper. Stir till combined.
Brush both sides of the steak with olive oil. Sprinkle the seasoning mixture on both sides and pat it in so it sticks.
Grill the steak for 4 to 5 minutes per side until it is medium doneness (and reaches an internal temperature of 135 to 145 degrees F on an instant-read thermometer).
Remove the steak from the grill and allow it to rest for at least 10 minutes before slicing.
Heat the flour tortillas on the grill, over a gas stove, or in a frying pan so they are toasty and crisped.
Slice the steak into thin strips. Then, dice into chunks.
Place the steak chunks in the tortillas and top with the avocado, cilantro, optional jalapenos and cheese, and a squeeze of lime juice.