Add butter and cheese to the bowl of a stand mixer fitted with the paddle attachment. Cream together until fully combined. Scrape down bowl sides and add flour. Mix on low speed until dough just comes together.

Turn dough out onto a strip of plastic wrap and shape into a 1 1/2" log. Wrap tightly in plastic wrap. If you have a spare wrapping paper or paper towel roll, slice it lengthwise and place the plastic covered dough log inside. (This is a nice trick for making shapely ice box cookies too.) Refrigerate the log for at least an hour and up to 4 days - or freeze for up to a month.

When you're ready to bake, place an oven rack in the center of the oven and preheat to 350 degrees. Line a large cookie sheet with parchment paper.

Slice the dough into 1/4" rounds. Arrange them on the prepared cookie sheet, spacing crackers about 1" apart.

Now make the egg wash; crack an egg in a small bowl and mix with a fork or whisk. Use a pastry brush to coat each cracker with egg wash. Optionally, press one Marcona almond into the center of each cracker.

Bake for 15 to 18 minutes, until firm and golden brown. Transfer crackers to cooling rack and lightly sprinkle with kosher salt.

Once crackers are cool, they'll keep for several days in an airtight container. (good luck with them lasting that long!)