Transparent Pie
["2 c. butter", "6 egg yolks", "2 c. sugar", "1 tsp. vanilla"]
["Preheat oven to 350\u00b0.", "Combine all ingredients and mix together until smooth.", "Pour into an unbaked pie shell and bake until done.", "Knife inserted in filling should come out clean."]
["butter", "egg yolks", "sugar", "vanilla"]