How to Make It
Beat butter and sugar at medium speed with an electric mixer until light and fluffy. Gradually add flour, beating at low speed until blended. Divide dough into 6 equal portions; roll each portion into a 12- x 1-inch strip. Place strips on lightly greased baking sheets.
Make a 1/2-inch-wide by 1/4-inch-deep indentation down center of each strip using the handle of a wooden spoon. Spoon half of jam evenly into indentations.
Bake at 350° for 15 minutes. Remove from oven; spoon remaining jam into indentations. Bake 5 more minutes or until lightly browned.
Whisk together powdered sugar, water, and extract; drizzle over warm shortbread. Cut each strip diagonally into 1-inch slices. Cool in pans on wire racks.