Add almond flour, coconut flour, xanthan gum, and salt to food processor and pulse until evenly combined.
Add butter and cream cheese and pulse for just a few seconds until crumbly.
Add in egg and vinegar and pulse until the dough just begins to come together (but stop before it forms into a ball).
Like with any pastry dough, make sure not to over-process the dough.
The mixture ought to resemble coarse breadcrumbs rather than cookie dough.
Turn out the dough onto cling film and form into a round.
Refrigerate for at least one hour, or up to 3 days.
Roll out dough between parchment paper, cut into desired size and pop it back into the fridge for 10-15 minutes prior to baking.
Brush with egg wash and sprinkle with garlic powder, caraway seeds and freshly ground black pepper.
Bake at 350°F/180°C for 17-20 minutes until lightly golden.
They will firm up while cooling.