Heat the oven to 425°F with a rack in the middle. Line a large rimmed baking sheet for easy cleanup.
Spread the tortilla chips in a single, slightly overlapping layer on the sheet so most chips are exposed.
Sprinkle the shredded Colby evenly over the chips, aiming to get cheese on nearly every chip. Distribute the pickled jalapeño slices evenly over the top.
Bake until the cheese is fully melted and bubbling and the chip edges are just starting to toast, 6–8 minutes; rotate the pan once for even melting. The nachos are done when the cheese is glossy and stretchy.
Serve immediately while hot, with salsa and sour cream alongside for dipping.