3 cups milk (720ml)
1/4 cup canned chipotle chiles (100g)
1.75oz butter (50 g)
1/3 cup plus 1 tbsp. all-purpose flour (50g)
2 ½ cups sharp cheddar cheese
2 tsp. dry prepared mustard (10g)
Prepare the milk by blending with the chipotle chile until smooth. Set aside.
In a heavy saucepan, make a roux by melting the butter, and then whisking in the flour. Once all of the butter has been absorbed by the flour, whisk in half of the prepared milk. Whisk until the mixture is thick and then add the remaining milk. Whisk in the dry prepared mustard. Continue to whisk while the sauce heats and thickens, about 1-2 minutes.
Serve immediately over warm vegetables.