Combine softened butter, brown sugar, salt and chai flavor and beat with an electric mixer or by hand, 2-3 minutes. Add flour, gently mixing by hand, until just incorporated. Press mixture into an 8 x 8-inch / 20 x 20-cm pan. Poke holes in dough with fork evenly over surface. Score dough with a knife or spatula into squares or rectangles. Chill about 30 minutes in fridge, meanwhile preheat oven to 325°F/160°C. Bake about 25 minutes or until edges are lightly browned. Remove cookies with a small spatula and cool. Decorate with icing colored with Watkins Food Coloring, as desired.
Makes 12 servings.