Heat a deep-fryer or a deep pot no more than half filled with oil to 325 degrees F.
Peel and slice potatoes to size of your desire and fry them for 2 minutes - this isn't to make them crispy, it is just to blanch them. Drain and cool fries.
Raise temperature of fryer or oil to 360 degrees F.
Add salt and pepper to the flour and combine. Take fries and dip first into the evaporated milk, shaking off excess, and then into the flour mixture, shaking off excess. Fry for about 5 minutes, until browned.