In Richard Linklater's film 'Boyhood,' the protagonist finds himself in an Austin Diner with his girlfriend late one night. They are being philosophical, and when she asks what they are doing there at three o'clock in the morning, he replies, "You know what we're doing here? Queso!" In Austin, In Austin, inviting places such as Kerbey Lane and Magnolia Cafe have long been popular spots for people to get their queso fix in the darker hours. This recipe is not specific to any particular place, but will remind you of late nights and good friends.
Note about chiles: Because of their thick skin, some fresh chiles need to be roasted and peeled before using. Here's how to do that: In a large, ovenproof skillet or on a baking sheet, place the chiles under the broiler 6 inches form the heating element. Cook until blackened, about 5 minutes per side. Place the chiles in a paper sack or plastic food-storage bag, close it tightly, and let it steam for 20 minute. To peel the chiles, remove them from the bag and gently rub off the skin.
In a medium saucepan, melt the butter over medium-low heat. Add the onion and jalapeños and cook, stirring occasionally, until softened, about 5 minutes. Add the garlic and Ananheims (see above note) and cook for 30 seconds longer.
Whisk together the cornstarch, milk, and water until well combined, then pour into the pan. Bring to a simmer, stirring constantly, and cook for a couple of minutes until the mixture begins to thicken. Add the cheese, turn down the heat to low, and cook, stirring, until the cheese has melted. Stir in the cilantro, cumin, cayenne, and salt, then taste and adjust the seasonings, if you like.
Transfer the queso to a serving bowl, a small slow cooker, or a chafing dish over a flame. Spoon guacamole and pico de gallo into the center of the queso. Serve warm with tortilla chips.