Pick out the nicest strawberries and set aside. Put the rest in a bowl and add the sugar, half the vanilla seeds and the vinegar. Squash together with the back of a fork and leave to macerate for 10–15 minutes.
Stir the rest of the vanilla seeds into the crème fraîche. To serve, spoon a little vanilla cream in the centre of each bowl, make a well in the middle and spoon in some mushed strawberries. Halve some of the reserved strawberries and sprinkle the lot over the vanilla cream. Scatter over the mint leaves and orange zest then serve.