Preheat oven to 350°F (175°C) and bake a pre-prepared tart shell until lightly golden. Let it cool.
In a saucepan, heat heavy cream until just simmering, then pour over chopped dark chocolate.
Stir until chocolate is completely melted and smooth to form ganache.
Pour ganache into the cooled tart shell and smooth the surface.
Chill in the refrigerator for at least 2–3 hours to set.
Decorate the top with mini chocolate eggs, edible flowers, or other festive toppings before serving.