Eclair Crust: In a medium saucepan, melt butter in water and bring to a boil. Remove from heat. Stir in flour. Mix in one egg at a time, mixing completely before adding another egg. Spread mixture into pan, covering the bottom and sides evenly. *If the sides of your pan are too greased you won’t be able to get the mixture to stay up the sides so make sure to just lightly grease.