Pour skim milk into saucepan and add instant coffee. Bring to a boil.
Remove from heat and set aside.
In a separate bowl, beat eggs together with sweetener.
Slowly add skim milk mixture to eggs and continue stirring.
Pour the mixture into four cups and bake in a water bath (bain-marie) for 20 minutes at 150°C.
Refrigerate for a few hours and serve chilled. Enjoy!