Soak gelatine in cold water. Cut the vanilla pod open lengthwise and scrape out the pulp. Bring the cream, 50 g sugar, vanilla pod and pulp to the boil and simmer at low heat for about 15 minutes.
Remove the pot from the stove and remove the vanilla pod. Squeeze out the gelatine and dissolve it in the hot, but no longer boiling cream.
Rinse four small moulds or cups (each with a capacity of approx. 1/8 l) with cold water. Spread the vanilla cream on top, cover and leave to cool for at least 6 hours (preferably overnight).
Wash and clean the strawberries, cut approx. 1/3 into slices or cubes. Puree the rest with lemon juice. Pass the puree through a fine sieve and season with 1-2 teaspoons of sugar.
Carefully remove panna cotta from the edge with a knife. Dip the panna cotta briefly in hot water up to the edge, then turn it over onto plates. Serve with purée and strawberries.