Cheesy Potatoes - cooking recipe

Ingredients

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

Preparation

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