Melt butter in a large skillet over medium high heat. Whisk in flour, until lightly browned, about 1 minute.

Add milk gradually and whisk until thick.

Remove from heat add cheese, salt & chives

Lay your bread slices on a baking tray.

Spread the pasta mixture onto the bread. Sprinkle cheese on top & grind fresh black pepper. Bake until cheese melted and breach slightly toasted.