Place shortbread down, fold smoked salmon to the size of shortbread, and place on top. Dollop crème fraiche with pastry bag in the corner of the shortbread on the salmon.

Drizzle olive oil over the salmon, sprinkle chives over the center, place the caviar mixture in a line diagonally starting from the top of the crème fraiche dollop, sprinkle flakey salt over the top, and serve.

Mix together right before use.

Mix oats, flour, 3.33 g salt, baking soda, black pepper, and brown sugar together in a bowl with a whisk until homogeneous.

Cut butter into chunks and work into dry ingredients with hands until evenly distributed with a semi-wet sand texture, then add water and mix just until evenly distributed. (The goal is to work the dough as little as possible so there is no gluten development).

Form dough into a ball and place it between two sheets of parchment before rolling out to 1/8 inch thick between the two sheets of parchment. Try to keep the dough as rectangular/square as possible for the best yield, and ensure it is an even 1/8 inch throughout.

Carefully transfer parchment with dough to a sheet tray and peel off the top layer of parchment (if parchment sticks, set it in the fridge for 10-20 minutes before removing). Using a 1.5 in x 1.5 in square cookie cutter, score the surface of the dough with as many squares as you can fit (the cookie cutter will not go all the way through the dough; score as deep as you can). Then cover and let rest in the fridge for at least 30 minutes.

While the dough is resting, preheat the oven to 350°F lowest possible fan. Once finished resting, uncover, sprinkle dough with remaining topping salt, place the sheet tray directly in the oven, and bake until golden brown, 12-15 minutes or longer if doing many trays at once.

Once golden, remove from oven (they should be dry and firm to the touch) and let cool for a couple of minutes before breaking along the score lines. They break best while still warm. Let cool completely before reserving in an airtight container with desiccants and oxygen absorbers for a maximum of 2 days before use. The fresher they are, the better, but I wouldn’t serve them after two days.