Napoleon - A Creamy Puff Pastry Cake
Now for the cream: Beat the eggs with the sugar and flour. Boil the milk. While the milk is warming, pour about 1/2 cup into the egg mix and stir well to gradually increase its temperature. This way the eggs won’t curdle when you add them to boiling milk. Repeat this step 2-3 more times as the milk approaches boiling temperature.