With a buttery shortbread base and warm jam center, they're the ultimate indulgence. A treat fit for the jolly sleigh-rider in all of us, but also a lovely treat any time of year!

Step 1

Separate egg, reserving egg whites. Cream butter, sugar and egg yolk. Add vanilla, flour and no-salt substitute and mix well.

Step 2

Shape dough into balls then roll each into the egg white mixture, then finely chopped walnuts. Place on cookie sheets about 2 inches apart. With thumb, dent each cookie.  Bake for 5 minutes.

Step 3

Remove cookies from oven. Ad a small amount of jam in each thumbprint. Bake for another 8 to 10 minutes.