Blackberry Sage Thumbprints
Preheat oven to 350. In a bowl, combine flour, cornmeal, sage and baking powder. Set aside.
In a large mixing bowl, beat butter on medium speed for 30 seconds. Add brown sugar. Beat until combined. Beat in egg yolks, lemon peel and vanilla until combined. Beat in as much flour mixture as you can with the mixer. Stir in remaining flour.
Shape dough into 3/4-inch balls. Place 1 inch apart on an ungreased cookie sheet. Lightly press the tip of your thumb into the center of each ball. Fill centers with about 1/4 teaspoon of the blackberry sage jelly.
Bake 10 minutes or until bottoms are lightly browned. Cool on cookie sheet for 1 minute. Transfer to wire rack, cool completely.