Shred 2 cups (about 8 oz) Monterey Jack cheese
Shred 1 cup (about 4 oz) cheddar cheese
In a saucepan over low heat, melt 2 tbsp butter
Whisk in 2 tbsp all-purpose flour until smooth
Slowly whisk in 1 1/2 cups milk (or evaporated milk) until thickened
Add 1/2 tsp garlic powder and 1/2 tsp salt (adjust to taste)
Reduce heat to low; add shredded cheeses a handful at a time
Stir until fully melted and smooth
Stir in 1/4 tsp ground cumin (optional)
Stir in 1/2 cup diced green chiles (optional)
If too thick, add a splash of milk; if too thin, simmer on low while stirring
Add chopped jalapeño or hot sauce (optional) to taste
Serve warm