Preheat the oven to 325 F. Spread half the tortilla chips on a rimmed baking sheet, sprinkle over half of the cheese, and then layer on the rest of the chips and cover with the rest of the cheese.
Place any and all of the desired toppings in individual bowls and place on the table, with small plates. Heat up the chili or taco meat, if using.
When ready to serve, bake the nachos for about 8 minutes until the cheese is melted. Transfer the nachos to a serving platter, and serve hot.
Notes
Leave space at one end of the table to place the tray of hot nachos with melted cheese. Put down a trivet or hot plate where the tray with the nachos will go.
Place the plates at the end of the table just before where the nachos will be.
Arrange the bowls for the toppings on the table. I like to put post-it notes in each bowl, reminding me of what will go into each bowl (e.g., sour cream, sliced jalapeños, diced onions, guacamole, etc.).
At the far end of the table, you'll want to have the napkins (lots of napkins) and forks (if you're using forks) so people can grab them after they assemble their nacho plates.
Then, fill the bowls with the toppings just before putting the nachos into the oven.
Make sure to heat any toppings that should be hot, like chili, browned ground meat, or taco meat.
Have plenty of chips and shredded or crumbled cheese on hand, so you can make new trays of nachos as the one on the table gets inhaled. When you see the nachos running low, assemble another tray and pop it onto the preheated oven.
Keep an eye on the toppings and replenish as needed.