Cheesy potatoes Obrien

2 lbs O'Brien potatoes (Frozen cubed hashbrowns with green and red peppers and onions)
1 pint half-and-half
1/2 cup margarine
1 small onion, chopped (optional)
1 (8 ounce) package Velveeta cheese, cubed
1 (8 ounce) package shredded cheddar cheese
salt and pepper, to taste


1 Add frozen potatoes to 13 X 9 pan, set aside.
2 In heavy sauce pan, over low heat,add half and half, margarine, onion, and cheeses and mix until melted and smooth, stirring frequently.
3 Add salt and pepper to taste.
4 Pour over potatoes.
5 Allow to set approximately 1 hour at room temperature.
(I have skipped this step and they have turned out fine!!)
6 Bake for one hour at 350 degrees until bubbly and lightly browned.