For the queso: Heat the butter in a small saucepan over medium heat. Whisk in the flour for 1 minute. Whisk in the milk and cook to thicken, about 2 minutes. Stir in the cheese to melt, then the green chilies. Season with salt and pepper.
For the beans: Place a medium size saucepot over medium heat and add the oil. Add the onion and garlic and cook for 2-3 minutes. Stir in the cumin and coriander and let cook for an additional minute, or until fragrant. Add water and bring to a simmer, then add the beans. Stir to combine and season with salt and pepper. The consistency should be pourable.
To serve, place a serving of chips in a bowl and pour a generous spoonful of beans over the top. Then pour some queso dip on top of that and garnish with pickled red onions and jalapeƱos.