Preheat the oven to 170°C. Lightly grease six 4-inch removable- bottom, fluted tart tins (square or round).
For the crust, stir the cookie crumbs with the melted butter until evenly combined. Divide this between the tins and press into the bottoms and up the sides. Bake the crusts for 10 minutes and cool while preparing the ganache.
For the ganache, heat the cream until it just begins to simmer and then pour this over the chopped chocolate. Let this sit a minute, then gently stir with a spatula starting at the centre and widening the circles until the chocolate has fully melted and the ganache is smooth. Stir in the vanilla.
Pour this into the tart shells and chill for at least 2 hours, until set. Remove the tarts from their tin using a small spatula and garnish with fresh berries, or dust tarts or even the berries with a little pearl or gold dust using a small brush.
The tarts are best served within a day of preparing.