Defrost 5 ounces frozen spinach completely. Squeeze out as much excess water as possible, then roughly chop the spinach.

Cut 16 ounces Velveeta queso blanco into large cubes.

Place a medium saucepan over medium-low heat. Add the cubed Velveeta and stir constantly until the cheese begins to melt and becomes smooth.

Pour in 1 1/4 cups whole milk and whisk or stir until the cheese and milk are fully incorporated and the mixture is smooth.

Stir in 1 1/2 cups prepared Pico de Gallo, the chopped spinach, 1/4 cup Parmesan cheese, and 1/4 teaspoon cayenne pepper. Continue stirring over low heat until the dip is hot and the ingredients are evenly combined. The dip will thicken slightly as it sits.

Transfer to a serving bowl and serve immediately with chips.