Tangerine Pudding

To prepare 2 cups of juice according to this recipe, you will need from six to eight tangerines. Feel free to replace it with any variety of oranges or tangerines if you want.
Whisk together the first 3 ingredients in a heavy 3-litre saucepan. Beat the tangerine juice until smooth. Remove 1 (2-inch) strip of peel from the tangerine using a vegetable peeler and add to the pan. Bring to a boil over medium-low heat, stirring occasionally; cook, stirring constantly, for 1 minute or until the mixture thickens and begins to bubble. Remove the pan from the heat.Beat the eggs until frothy. Gradually whisk in 1/4 cup of the hot juice mixture with the eggs; add the egg mixture to the remaining hot juice mixture, whisking constantly. Return to the heat and cook, stirring constantly, for 2 minutes or until thickened. Transfer the mixture to a medium bowl; add the butter and the next 2 ingredients until the butter is melted. Wrap the warm custard directly in a thick plastic wrap (so that no film forms); refrigerate for 2 hours. (The mixture will thicken as it cools.) Peel if desired. Serve with whipped cream.