In a large bowl beat the egg yolks with a whisk.

In a saucepan, add the water, sugar, cinnamon, lemon peel. Stir then simmer until it starts to bubble. Remove the saucepan from the heat. Discard the lemon peel and remove but reserve the cinnamon stick if using. Allow the mixture to cool.

Slowly, add the watery sugar mixture to the beaten egg yolks. Using a whisk combine it slowly. Too much mixing will cause the mixture to froth.

Add the egg mixture back into a saucepan over a low heat for about 25 minutes or until the egg mixture has thickened you want it a similar consistency to thick custard. Stir occasionally.

When done, discard the cinnamon stick and allow the egg mixture to completely cool before decorating or filling a cake.