Smoked Sausage & Potato Casserole

This was a good casserole.  Not the quickest since you have to cook everything first, but as Mike said "I love anything with cheese!"

3 cups idaho potatoes, peeled, boiled and cut into cubes when cool, approx. 1 lb
4 tablespoons butter
4 tablespoons flour
2 cups milk
1/2 teaspoon salt
1/4 teaspoon pepper
1/2 lb Velveeta cheese, diced
1/2 cup sharp cheddar cheese, shredded
1 lb skinless smoked sausage 
1 onion
1 red pepper1/8 teaspoon paprika
Directions:

1
Cut skinless smoked sausage in half, lengthwise, and then chop into 1/2 inch "half moon" cuts.  Chop onion and red pepper.  Combine and Cook in a frying pan for about 15 minutes, turning frequently until sausage is slightly brown and onions are translucent.
2
Meanwhile, put cooked & diced potatoes in 2 quart casserole. Add cooked meat/veggie and give it a gentle toss.
3
Mix all remaining ingredients (except for shredded cheddar cheese & the paprika) in a saucepan over medium heat until warm, melted and smooth. (Use a whisk and stir constantly.).
4
Pour cheese sauce over potatoes and meat. Sprinkle shredded sharp cheddar cheese on top, and then sprinkle paprika evenly over the top.
5
Bake in preheated 350°F oven for 35-45 minutes (watch, until golden brown on top).
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