French egg casserole

-----------Ingredient --------

• 1/4 c. butter
• 1/4 c. flour
• 1 c. non dairy creamer
• 2 c. boiling water
• 3/4 tsp. salt
• 1/4 tsp. cayenne pepper
• 1/2 lb. Gruyere cheese, grated
• Pinch black pepper
• 1 tbsp. prepared mustard
• 2 egg yolks, beaten
• 2 tbsp. water
• 1/2 c. butter
• 4 lg. onions, thinly sliced
• 1/4 lb. fresh mushrooms, thinly sliced
• 12 hard boiled eggs, quartered,Paprika

--------------Preparation Method-------------

In heavy saucepan, melt 1/4 cup butter, blend in flour, stirring for 1 minute. Do not allow to brown. Add creamer, then boiling water all at once, beating to blend. Increase heat to moderately high stirring constantly until it boils and thickens. Fold in seasonings, cheese and mustard. Continue stirring and cook ONLY until cheese melts. Remove from fire; add egg yolks which have been beaten with 2 tablespoons water. Return to fire and heat to JUST heated through. DO NOT BOIL! Melt butter (1/2 cup) in a skillet; saute onions until tender. Remove onions. Saute mushrooms in same pan until tender. Mix onions and mushrooms and pour into shallow 2 quart casserole. Blend in 1 cup of the sauce you made. Lay quartered hard boiled eggs and lay over onions and mushrooms. Top with remaining sauce and sprinkle with black pepper and paprika. Cook at 350 degrees in oven for 15 minutes. Brown briefly under broiler; stay right by oven door and WATCH so it doesn't burn.