Milk eggs, a grandmother’s recipe with an incomparable taste

Milk eggs, a grandmother’s recipe with an incomparable taste
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The ingredients:
1L of milk (preferably whole for a creamier dessert but it also works with semi-skimmed milk)
100g of white sugar
1 or 2 sachets of vanilla sugar (depending on your taste) (optional)
2 tsp of flavoring vanilla (optional) OR 2 tbsp of rum (vanilla or rum depending on your taste)
6 eggs
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Preparation:
Boil the milk with the sugar, vanilla sugar and vanilla. Then you remove it from the heat (yes, the milk boils over quickly, be careful), and you let it cool a little (just long enough to prepare the eggs).