Prepare the ingredients: Prepare the ingredients as listed above.

Preheat: Set the oven broiler to low.

Make the guacamole: Mash the avocado in a bowl with a fork until smooth. Mix in the red onion, lemon juice, and cilantro. Season with salt and pepper to taste. Refrigerate until ready to serve.

Cook the beef: Heat a nonstick pan over medium heat. Add the ground beef, onion powder, cumin, garlic powder, paprika, and chili powder. Break up the beef into small pieces using a spatula. Cook until the beef is no longer pink. Season with salt and pepper.

Assemble nachos: Spread the tortilla chips on a baking sheet. Spoon the beef mixture over the chips. Top with all three cheeses and the refried beans.

Broil: Place the tray under the broiler and heat until the cheese is fully melted.

Serve: Remove the nachos from the oven and top with romaine lettuce, tomato, jalapeño (if using), red onion, sour cream, and guacamole. Enjoy with a cold beer.