Preheat the oven to 350°F. Line two baking sheets with parchment paper and set aside.
In a large bowl, beat the sugars with the vanilla bean seeds until well combined. If not using vanilla bean seeds, skip to the next step.
Cream butter and sugars until light and fluffy, 1-2 minutes. Scrape down the sides of the bowl. Add the egg and milk and, if using, vanilla extract. Beat until well incorporated, 30 seconds to one minute.
Add the dry ingredients and mix on low speed until combined.
Fill a pastry bag fitted with a large round tip with the cookie batter/dough. Pipe small (1 inch) disks/kisses onto the parchment, spaced 2 inches apart. Don't worry about the point when you pipe them. They will spread slightly and the point will disappear.
Bake for approximately 13-16 minutes, or until golden brown, especially around the edges and the bottom.
Allow to cool before serving. Store in a glass container or jar to keep them from losing their crispness.