Spread the tortilla chips in an even single layer on a large ovenproof platter or sheet pan. For serving to multiple people, arrange in overlapping layers leaving space for cheese sauce to coat chips.

Cheese Sauce

Make roux

In a medium saucepan over medium heat, melt the butter. Whisk in the flour and cook, whisking constantly, for 1 to 2 minutes until the mixture is lightly golden and fragrant (this removes the raw flour taste).

Add dairy

Slowly whisk in the whole milk and half-and-half, a little at a time, until smooth. Continue to cook over medium heat, whisking frequently, until the mixture thickens and coats the back of a spoon, about 4 to 6 minutes.

Finish sauce

Reduce heat to low. Stir in the grated sharp cheddar and pepper jack in batches, allowing each addition to melt before adding more. Whisk until the sauce is smooth and glossy. Stir in the mustard, worcestershire sauce, 3 tsp kosher salt and black pepper. Taste and adjust seasoning if needed. Keep warm over the lowest heat, stirring occasionally so it doesn’t skin.

Hot Pepper Mix

Prepare mix

In a medium bowl combine the chopped pickled jalapeños, sliced banana peppers, minced fresh chile (if using), olive oil, diced red onion, chopped cilantro, lime juice, sugar and 1/2 tsp kosher salt. Toss to combine and let sit for 5 to 10 minutes to allow flavors to marry.

Assemble & Garnish

Top chips

Ladle the warm cheese sauce over the arranged chips, distributing evenly so most chips are coated. If using a sheet pan, you can also drizzle some sauce, then return to a 300°F (150°C) oven for 5 minutes to warm through and help the sauce set slightly.

Add hot pepper mix

Spoon the hot pepper mix over the sauced chips, distributing peppers and onions so each portion has some of the tangy heat.

Finish and serve

Scatter the sliced green onions over the top, add optional diced tomato and crumbled cotija if using. Serve immediately while cheese is warm. Provide extra lime wedges on the side if desired.