How to cook
Leave the eggs at room temperature a day ahead of time to temper it. The gelatin is soaked for 10 minutes, then melted in a water bath. 2 cups (500 ml) of the milk is heated in a water bath.
The yolks are beaten down with the sugar until whitened. Dissolve the flour with 2/5 cup (100 ml) of milk and pour it into the beaten egg yolks. Pour this mixture into the heated milk while stirring. After removing from the fire, let it stand for 5 minutes, then add the melted gelatin. The egg whites are beaten down into snow.
Unlike the cream, the egg whites need to be at room temperature and whipped in a perfectly clean, dry container, and you need to make sure no egg yolk or fat falls into them. First add the beaten egg whites to the slightly cooled but still hot milk, gradually while whipping with a whisk. Then whip the liquid cream.
The liquid cream and bowl you whip it in needs to be very cold, but not frozen and even the whisk must also be at refrigerator temperature. This will make it fluffy quickly. Otherwise, there is a risk of it curdling and for the butter to float up to the top.