Title: Buttermilk blue potatoes au gratin
 Categories: Potatoes
      Yield: 6 Servings
 
      7 md Maine russet potatoes;
           - parboiled, peeled,
           - and thinly sliced
  2 1/2 tb Unsalted butter
      1    Garlic clove; crushed
      2    Shallots or green onions;
           - minced
      2 tb Unbleached flour
  1 1/2 c  Milk; at room temperature
      1 c  Buttermilk; at room temp
      1 ts White pepper
    1/4 c  Mayonnaise
      1 ts Dijon mustard
    1/4 ts Worcestershire sauce
    1/4 c  Fresh parsley; chopped
      2 oz Blue cheese; crumbled,
           - divided
      3 c  Raw mushrooms; sliced
      1 c  Monterey jack; grated
  1 1/2 c  Potato chips; coarsely
           - crushed
      1    (10 oz) pkg frozen
           - chopped broccoli; thawed
      1 tb Canned pimento; diced
 
  Arrange half of the potatoes in the bottom of a buttered 2 1/2-quart
  shallow casserole dish.  Make the buttermilk-blue cheese sauce as
  follows: melt butter in a medium saucepan over low heat. Add garlic
  and shallots and saute for 1 minute.  Add flour, stir, and cook for 3
  minutes more. Pour in milk and buttermilk all at once. Cook, stirring
  constantly, until sauce thickens and bubbles.  Remove from heat and
  stir in white pepper, mayonnaise, mustard, Worcestershire, parsley
  and half of the blue cheese. Layer all the mushrooms over the
  potatoes in the casserole; top with half of the sauce and distribute
  the grated jack cheese over the sauce. Layer remaining potatoes over
  cheese and spoon remaining sauce on top. Sprinkle with remaining blue
  cheese. Bake at 350F for 45 minutes. Sprinkle potato chips over top
  and bake an additional 10 minutes. Meanwhile, blanch the broccoli.
  Arrange broccoli around outer edges of casserole and garnish with
  pimento; bake 5 minutes longer.