My aunt Jagica's cookies with jam

Directions

1. In the bowl beat the butter, shortening and sugar until smooth ( 2-3 minutes ). Beat in the vanilla and lemon zest.
2. Gently stir in the flour just until incorporated.
3. Flatten the dough into 4 disks, wrap in plastic wrap, and chill the dough until firm but not hard (30 minutes).
4. Preheat oven to 350F with the rack in the middle of the oven.
5. Roll out the dough between two parchment papers.
6. Use a cookie cutter of your choice to cut out the cookies. Make sure you put the same size cookies on the baking sheet for even baking.
7. Bake for 6 - 8 minutes for smaller cookies, or until the cookies change colour.
8. Using a small knife place a jam on a whole cookie, place a cookie with a hole over the whole cookie, repeat.
9. You can use different jams.