Frank's Cream Of Crab Soup

My uncle frank makes the best cream of crab soup! He luckily gave me the recipe... It's wonderful!!

In soup pot , melt the butter over medium heat.

Add onion , saute for 2-3 minutes.

Add potatoes , old bay , and mustard.

Decrease heat to low , cook , stirring often until potatoes are barely tender.

Remove from heat.

Whisk in flour , salt and pepper.

Return to medium heat and stir constantly about 2 minutes.

Slowly pour in half and half and milk , stirring constantly.

Cook over med-low heat , stirring often until thickened.

Add the crabmeat , simmer about 15-20 minutes.

When ready to serve , stir in sherry and parsley.

butter, potatoes, onion, dry mustard, salt, old bay seasoning, flour, pepper, half-and-half, milk, crabmeat, dry sherry, parsley