Clean, wash and slice the rhubarb. Wash the strawberries, drain well, clean and cut in half. Bring 300 g strawberries, rhubarb, currant juice, 125 g sugar and lemon peel to the boil in a pot.
Let the fruits boil for about 1 minute. Stir pudding powder and about 5 tablespoons of cold water until smooth and stir into the fruit mass. Let it boil again for about 1 minute. Remove the lemon peel and add the remaining strawberries to the groats.
Pour into a glass bowl and let it cool down. For the sauce, take off about 3 tablespoons of the milk and mix with the sauce powder and the remaining sugar. Bring the remaining milk to the boil, remove from the heat and stir in the sauce powder.
Bring to the boil again briefly. Cover sauce with cling film and let it cool down. Whip cream until semi-stiff. Stir the cooled down sauce well and fold in the cream. Serve in a sauciûre. Decorate the groats with a lemon spiral, lemon balm leaves and a halved strawberry as desired.
Serve with the sauce.