Classic Potatoes au Gratin

This is a recipe from my collection that I have not tried for years. Needless to say, I made it the other night and it was delicious! You can file this one under "comfort food".

Ingredients:

6 cups thinly sliced potatoes

1/4 cup butter or margarine

1/4 cup flour

1 tsp. salt

1/2 tsp. dry mustard

1/4 tsp. pepper

2 1/2 cups milk

2 cups cheddar cheese, grated

2 Tb. onion

Preheat oven to 350 degrees f.

Cut potatoes into thin slices. I used a slicer, but would not do this again as the potatoes did not cook evenly due to the uneven width. Put the potatoes in water so they do not go brown.

Melt butter in medium saucepan over medium heat.

Add flour

Add salt, pepper and mustard.

And blend

Gradually add milk;

cook, stirring constantly until thickened.

Add 1 1/2 cups cheese and onion

I used red onion, but you can use whatever you have

Stir until cheese is melted

In 2 quart casserole dish, alternate layers of potatoes and cheese sauce.

Bake 1 hour and 15 minutes or until potates are tender.

Top with remaining 1/2 cup cheese; continue baking 5 minutes or until cheese is melted.