Preheat the oven to 375 degrees.
Peel and slice the potatoes. Put them in a greased 8 x 8 pan.
Add the ham.(if using)
Add the salt and pepper.
Add the flour to a bowl and add a little of the milk. Stir until almost no lumps remain. Add to the potatoes.
Pour the milk over the potatoes. Make sure it almost covers it, if a few stick up don't worry about it.
Bake the scalloped potatoes for about 1 hour 30 minutes. If it starts to get to brown cover with foil. Let set 10 minutes before serving.