First prepare the crust by combining the flour, cocoa powder, baking soda & confectioner's sugar together in a large mixing bowl.
Add the softened vegan butter & cream it on low speed until it comes together to a crumbly dough.
Add the vanilla extract & continue mixing until it comes together to a soft pliable dough.
Wrap dough in plastic wrap & refrigerate for at least 1 hour
Meanwhile prepare the frangipane by combining the enerG egg replacer with the warm water & whisk smooth.
Break up the almond paste into the work bowl of your mixer & mix it on low speed to smooth out.
Add some of the egg replacer mixture to help it smooth it out then add the rest.
Add the softened vegan butter & mix smooth
Add the vanilla extract & then flour last~ Mix to a smooth paste.
Roll the chilled shortbread dough to fit into a 9" tart shell with a removable bottom
Spread ½ cup of the apricot jam into the bottom of the unbaked crust then pipe the frangipane over top (*It's easier to use a pastry bag rather than try to spread it with a spatula because as it will have a tendency to mix into the jam rather than keep clear separated layers)
Arrange the sliced apricots over top and sprinkle with sugar *optional
Bake in a preheated 375°F oven for approximately 50 minutes or until the frangipane is baked through and no longer raw in the center. The frangipane will be slightly puffed and golden browned.
Cool slightly then glaze with the remaining apricot jam that has been melted in a small sauce pot with a tablespoon of water