Add cookies with cream filling into a blender (or food processor) and crush until finely ground. Transfer crumbs to a medium bowl, add melted butter, and mix until crumbs are evenly moistened. Press the mixture onto the bottom and up the sides of an 9 or 9,5-inch (23/24cm) tart panor a another pan with removable bottom. Place in the freezer for 15 minutes (or in the fridge for 30 minutes) to firm up while you make the filling.
Blueberry Blackberry Mousse Filling
Add the blackberries and blueberries into a blender and blend until smooth. (Optionally, strain the berry purée through a mesh sieve and discard the seeds. Then put back into the blender.) Add vegan cream cheese, sugar and vanilla and blend until smooth. Set aside.
In a mixing bowl, whip up the cold non-dairy whipping cream using a handheld mixer, until stiff peaks form. Refrigerate until ready to use.
In a small saucepan, stir the agar-agar into the non-dairy milk. Bring to a boil and cook for about 2 minutes or according to the package instructions. Remove from heat and let cool slightly, stirring occasionally. (If using gelatin, you can skip this step. Read recipe notes*).
Gently fold the agar-agar mixture into the berry purée mixture, then fold in the whipped cream. Stir just until combined. Fill the mixture into the prepared tart pan, smoothing out evenly, and refrigerate for 4 hours at least or better overnight to firm up.
When the mousse is firm, you can remove the tart by gently pressing against the removable bottom of your pan. Decorate your tart with fruits or other toppings, and serve chilled.
If you want a crisper and less soft crust, you can bake it in a 350°F (175°C) preheated oven for 5-6 minutes, then let cool completely before adding the filling.
If you want to use drained yogurt, check out this blog post about how to drain yogurt.
If you don't find non-dairy whipping cream or pure coconut cream, you can use 1-2 cans full-fat coconut milk. Just chill them overnight, then scrape the solid cream off the top, discarding the liquid.
Please make sure to use 100% agar-agar powder, or you may need more.
If making this tart non-vegan, you can use regular cream cheese, heavy whipping cream, and gelatin. If using powdered ready to use gelatin (no soaking or cooking required), you can skip step 3. Simply add the powdered gelatin into the berry purée in step 1 along with the cream cheese.
Nutrition is calculated automatically and should be used as estimate.