1 Cup unsalted butter, warmed to room temperature
1/2 Cup golden brown sugar, tightly packed
1-1/2 tsp Saigon Cinnamon
1/2 tsp Allspice, Ground
2-1/4 Cups all-purpose flour
1/4 tsp Kosher salt
1/4 Cup Cinnamon Sugar
With an electric mixer, beat the room-temperature butter with the brown sugar until mixture is light and fluffy (about 2-3 minutes). Add the ground cinnamon and beat to incorporate.
Add the flour and salt to the mixing bowl, and mix on low speed until the dough just begins to come together, being careful not to over-mix. If the dough is crumbly, use your clean, bare hand to gently knead it until it comes together. Transfer the dough from the mixing bowl to a large piece of waxed paper.
Use a rolling pin to roll the dough out into a 9″ x 10-1/2″ rectangle. The dough should be consistently about 1/4″ thick. Place another sheet of waxed paper on top of the dough, and wrap the wax-papered cookie dough in plastic wrap, or place in a large ziploc-type plastic bag.
Chill the dough in the refrigerator for at least one hour.
Preheat the oven to 300°F and line two rimmed baking sheets with parchment paper. Use a cookie cutter to cut out shapes from the dough, and transfer them gently to the parchment-lined baking sheets.
Sprinkle cookies with the Cinnamon Sugar and bake for 18-20 minutes, until shortbread are just lightly golden, but not yet browned around the edges.
Remove baking sheets from oven. Allow shortbread to cool 1-2 minutes before transferring to wire cooling racks, and allowing the cookies to cool completely before serving.