Heat your gas or charcoal grill to high (Here's how to tell if it's high: Hold your hand about four inches above the cooking surface. After 2 to 3 seconds, the heat will force you to pull your hand away).
Oil the grill grate, using an oiled rag.
Rub steak with taco seasoning on both sides and place on the grill. Use these cooking times to cook your steak to medium: 2 to 3 minutes per side for a 1/2-inch thick steak, 4 to 6 minutes per side for a 1-inch thick steak, 6 to 9 minutes per side for a 1 1/2 to 2-inch thick steak.
Take the steak off the grill. Let rest 2 to 3 minutes to allow the juices to reabsorb into the steak, then slice thinly.
Preheat broiler to high. Line a large (11x17) baking sheet with aluminum foil.
Arrange half of the tortilla chips in one layer on the baking sheet. Sprinkle with half of the steak, onions, tomato, olives, and jalapeno; top with half of the cheese.
Repeat layers with remaining ingredients.
Broil about 4 inches from the heat source for about 3 minutes to melt the cheese and brown the top layer slightly.
If you don't like vegetables on your nachos skip everything but the steak, cheese, and chips.