Grind all the ingredients for a tart base in a blender. Put the resulting crumbs in a mold, carefully compact and place in the oven for 10 minutes. Cool the base completely in the refrigerator.
In a stewpan, mix all the components of the berry layer. After the mixture boils, punch it with a submersible blender, then pour over the top of the tart. Cool completely.
Grind the chocolate. Combine butter and cream in a saucepan and bring the mixture to a boil. Add chocolate and stir until smooth.
Pour the chocolate mixture over the berry and cool the tart completely. Garnish with berries, almonds, cocoa nibs or something else delicious and rhyme with tart.