1. You can start with the recipe by preheating the oven to 350 degrees Fahrenheit.
2. Proceed to melt the butter in a small saucepan, then add the flour.
3. You can now go ahead and season with salt and pepper after whisking in the milk.
4. Then proceed to cook – stirring periodically with a whisk – until the sauce is smooth and boiling.
5. Reduce the heat to low and add 1 cup of cheddar cheese.
6. Half of the sliced potatoes should be placed in a lightly greased 1.5-quart casserole dish.
7. Then proceed to make sure half of the cheese sauce should be poured over the potatoes.
8. You can then place the second layer of potatoes and cheese sauce on top of the first. The remaining ½ cup of cheddar cheese should be sprinkled on top.
9. To add some color, you can sprinkle with paprika.
10. At 350°F, bake for about 1 hour, uncovered.

You can watch this video recipe to know how to cook scallop potatoes.