The best way to get crispy nachos is to set the oven to 350F and in a single layer, add nachos, then the dry ingredients (cheese, olives, onions, chives, etc) then a few minutes before the cheese is melted, add the wetter ingredients like diced tomatoes, chili, etc. You just want it warm, not cooked. This will prevent the chips from getting soggy and they will be crisp enough to hold the toppings as you lift them off one at a time. Put the salsa, guacamole, jalapeños and sour cream off to the side. Allow guests to spoon them on to the nachos or their plate, as many do not care for these extra wet toppings that are only going to weigh the chip down.