In a medium skillet over medium heat, heat dried beef slices.
Allow to heat through and add some grease to the pan.
With a slotted spoon, remove to a platter, while leaving as much grease behind as possible.
Whisk in flour all at once to form a roux.
Whisk in milk, a little at a time, increase heat to medium-high, and cook, stirring, until thickened.
Bring to a boil, stir in beef, salt, and pepper.
Heat through and serve over toast.