Put the flour and butter in a small pot
Stir the flour and butter together over low heat until they start to foam and bubble
Keep cooking and whisking the bubbly mix for another minute or so
Add the milk and mix it in with the butter and flour
Raise the heat a little and whisk the milk while it comes to a boil
When the blend gets to a simmer, it will get thicker
Turn off the heat when it gets thick enough to cover a spoon
Add a handful of chopped cheddar at a time and stir it into the sauce until it melts
Put the pot over a low heat if you need to help the cheese melt. The cheese sauce shouldn't get too hot
Add the salt and pepper powder and stir them in after all the cheese has melted into the sauce
Check the salt and make any necessary changes
If the sauce gets too thick, just add a little more milk and mix it in
