Spiced Shortbread Cookies

FOR THE SHORTBREAD DOUGH:

1. Transfer the sugar to a mini food processor and pulse for 20-30 seconds until the sugar is very fine. (Don't take the lid off the food processor too quickly, because there will be a sugar cloud).
2. In the bowl of a stand mixer, combine the flour, sugar, cinnamon, ginger, allspice and salt. Whisk to combine.
3. With the stand mixer running on low speed, add the butter one tablespoon at a time over 1-2 minutes until the mixture resembles wet sand.
4. Add the cream cheese, vanilla and lemon zest and mix on medium speed until the dough forms a cohesive mass.
5. Transfer the dough to a work surface and form it into a ball. Cut the ball into two equal portions and form each one into a round flat disc about ¾" to 1" thick. Wrap each disc in plastic wrap and refrigerate for 30 minutes.
6. Preheat the oven to 375°. Line a baking sheet with parchment paper or silpat and set aside. Note you can bake two pans of cookies at once, but you'll want to swap them about half way through cooking if you have them on separate racks.
7. Work with one disc of chilled dough at a time. Sandwich the dough between two pieces of parchment paper or plastic wrap and use a rolling pin to roll the dough to ⅛" inch thick or about the thickness of two quarters stacked. Place the rolled dough on a baking sheet (for stability) and refrigerate for 10 minutes. (Note: this dough is easier to work with when chilled. If it starts to get warm, just stick it in the refrigerator for a few minutes.)
8. EMBOSSING: This is optional, but if you want to fancy-up the cookies go for it. If you have a cookie stamp, you can use it to emboss the cookies with a decorative design. Be sure the cookie dough is well chilled before embossing.If you don't have an embossing stamp (I don't) use household items that will leave a pattern. Dip the end of chopsticks halfway into the cookies for small round divots that you can create a pattern with.Use the tines of a fork to prick the dough, or lightly run them across the face of the dough to create a striated pattern.
9. Once chilled, use your favorite seasonal cookie cutters or 1½" to 2" biscuit cutters to cut out the cookies and transfer them to the prepared sheet pan. Bake for 8-10 minutes (depending on how large the cookies are), spinning the pan(s) 180° halfway through cooking. When the cookies are lightly golden on the edges, remove them from the oven and cool on the sheet pan for 2 minutes, then transfer to a wire rack to cool completely.
10. Continue cutting and baking cookies in the same method.

FOR THE GLAZE:

1. In a small saucepan melt the butter over medium heat. Remove the pan from the burner and stir in the powdered sugar, vanilla and 1 tablespoon of warm water at a time and whisk until smooth. If your glaze is too thick, add more water 1 teaspoon at a time. If it's too thin, add a little more powdered sugar.
2. Brush the glaze over the face of the cookies and immediately sprinkle with your favorite sparkling sugar, non-pareils or decorating confections. Let the cookies dry completely before transferring them to an airtight container.