01 - In a medium saucepan, melt 2 tablespoons unsalted butter over medium heat. Whisk in 2 tablespoons all-purpose flour and cook for 1 minute, stirring constantly, to form a roux.
02 - Slowly whisk in 1 cup whole milk, ensuring no lumps form. Continue to cook, stirring frequently, until the mixture thickens to a creamy consistency, approximately 2 to 3 minutes.
03 - Reduce the heat to low. Gradually stir in 1 cup shredded cheddar cheese and 1 cup shredded Monterey Jack cheese until they are fully melted and the sauce is smooth. Incorporate 1/2 teaspoon garlic powder, 1/2 teaspoon onion powder, 1/4 teaspoon ground cumin, 1/4 teaspoon smoked paprika, and 1/4 teaspoon salt. If desired, stir in 1 finely diced jalapeño and 1 (10 ounce) can of drained diced tomatoes with green chilies. Keep the queso warm over low heat, stirring occasionally to prevent sticking.
04 - Place 2 large bags (approximately 24 ounces total) of tortilla chips in a spacious serving bowl or spread them evenly across a large serving tray, ready for assembly.
05 - Warm your chosen protein options: 2 cups of cooked, seasoned ground beef or turkey, 2 cups of shredded rotisserie chicken, or 2 cups of drained and rinsed cooked black beans. Transfer each prepared protein into separate serving bowls.
06 - Organize the various toppings into individual serving bowls for convenient self-service. These include 2 cups shredded lettuce, 2 cups diced tomatoes, 1 cup sliced black olives, 1 cup pickled jalapeños, 1 cup sliced green onions, 1 cup sour cream, 1 cup guacamole, 1/2 cup chopped fresh cilantro, and 2 lime wedges.
07 - Present the arranged tortilla chips, the warm queso sauce, the prepared protein options, and all the various toppings. Instruct guests to customize their nacho plates by layering chips with their chosen ingredients and a generous drizzle of the warm, creamy queso sauce.