This particular meal started with browning some ground beef in a cast iron skillet with minced onions, garlic, and Serrano chili. Add salt, ground pepper and dried chipotle to taste. Drain liquid fats, if necessary to keep the nachos from getting soggy.
Layer a handful of tortilla chips in a microwave or ovenproof dish, or several handfuls if you are feeding a crowd and using a big dish. Top with half the meat, some finely diced tomatoes, chopped green onions and more chilies if desired. Cover amply with shredded mixed cheeses, I use the Kirkland brand Mexican Style End shredded cheese from Costco. Repeat with another layer of chips and toppings.
Microwave or cook in a medium-hot oven until the cheese is melted and toppings are heated through. Remove from oven and dot with sour cream and some reserved scallions. If I'd had any avocado, that would have gone on at the end as well.
I usually only make enough for myself so I just dig in and eat from the dish but serving to a plate is possible with tongs, two spoons, or hands.
Other good additions would include salsa at serving, and diced sweet peppers either added to the browning meat (as I think I did in this picture) or layered in with the tomatoes.