First, de-stalk your strawberries and place them in a pan with the sugar. Heat gently until the strawberries stew down slightly and some of their juices come out.
Lightly whip the cream with the seeds from the vanilla pod, and then stir in the yoghurt.
Divide the rum babas or madeleines between 4 dessert glasses and spoon the strawberries, cream and custard in layers on top. Decorate with halved strawberries and mint leaves, then serve.