Mix pitted Hojiblanca black olives with peeled and degermed garlic clove and add olive oil.
Set aside 1/6 of this mixture, called an olivade.
While continuing to blend, add whipping cream in a stream until you get the right consistency.
Place in a pastry bag and set aside.
Preheat oven to 350°F.
Place flour, butter, almond powder, and remaining 1/6 of olivade in a bowl.
Blend mixture with your fingers until it resembles coarse sand.
Spread on a baking sheet lined with parchment paper and bake for 20 minutes.
Cut remaining pitted Hojiblanca black olives into slices.
Fill verrines halfway with cream mixture, top with a few Hojiblanca black olive slices, and finish with a little crumble and a sprig of chervil.