Apple-Lemon Filling

• 3/4 cup sugar
• 1 tablespoon flour
• 3 tablespoons lemon juice
• 1 tablespoon cold water
• 1 egg
• pinch of salt
• 1 apple, pared and grated

Mix sugar and flour in saucepan; add lemon juice, cold water, beaten egg, salt and apple. Boil 2 minutes, stirring constantly. Cool before spreading