Melt the chocolate gently over a double boiler until smooth. Let it cool slightly.
Using a whisk or standing mixer with a whisk attachment, whip the cream, sugar, and vanilla until firm peaks begin to form.
Fold the melted chocolate into the whipped cream. It will thicken as the chocolate cools.
Refrigerate 1–2 hours until set.
FOR MINI TART ASSEMBLY:
In a 2" wide dome silicone mold, use a piping bag to fill each cavity. Tap silicone mold to knock out any air bubbles that would prevent the mousse from providing a sturdy structure for any next steps/
Leave uncovered for an hour and place in freezer to chill. After one hour, remove from freezer, cover in plastic, and freeze overnight.
After 12- 24 hours, carefully unmold the mousse domes and set on a speed rack over a sheet tray for next steps/
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