Combine butter or margarine and water in a saucepan and stir over moderate heat until butter melts. Add flour all at once and stir vigorously about 1 minute, or until mixture forms a ball and leaves the sides of the pan. Remove from heat. Add eggs, one at a time, beating thoroughly after each addition with a wooden spoon or an electric mixer. Continue beating about 1 minute until a spoonful of the mixture breaks away sharply from the rest of the mixture.
Drop by heaping tablespoonfuls on an ungreased baking sheet. Bake in a hot oven at 425 degrees F for 35-50 minutes. Cool on a rack.
When cooled, gently split puffs crosswise and fill with pudding mixture. *I use a pastry bag and long tip. You can also cover with a chocolate glaze - melt 2 blocks unsweetened chocolate and 2 Tbsp. butter or margarine. Stir in 1 cup powdered sugar alternately with 4 Tbsp. milk. Beat until smooth and shiny. Spoon or drizzle over the top of the puffs.