Preheat oven to 375 degrees F. In a large bowl, beat butter with an electric mixer on medium to high speed for 30 seconds. Add the sugar, baking soda, cream of tarter, and cinnamon. Beat until combined, scraping sides of bowl occasionally. Beat in egg and vanilla until combined. Beat in ground almonds. Beat in as much of the flour as you can with the mixer. Using a wooden spoon, stir in any remaining flour.
Shape dough into 1-inch balls, or scoop dough with a 1-inch cookie scoop. Place balls 2 inches apart on an ungreased cookie sheet. Bake about 13 minutes or until cookies are light brown. Transfer cookies to a wire rack; cool.
Drizzle cookies with Browned Butter Drizzle.
In a small saucepan, heat butter over medium heat until butter turns the color of light brown sugar, stirring frequently.
Remove from heat. Slowly stir in powdered sugar, vanilla, and enough milk to make of drizzling consistency.