Preheat oven to 350°F (175°C).

In a medium mixing bowl, cream together the brown sugar and shortening until light and fluffy.

Beat in the eggs, milk, and grated orange rind.

In a separate bowl, stir together the baking powder, ground cinnamon, ground clove, salt, and flour.

Gradually mix the dry ingredients into the wet ingredients until just combined.

Stir in the raisins and chopped walnuts (if using).

Drop the cookie dough by teaspoonfuls onto greased cookie sheets, leaving some space between each cookie.

Bake in the preheated oven for 10-12 minutes, or until the edges are lightly golden brown.

Remove the cookie sheets from the oven and let the cookies cool on the baking sheets for a few minutes before transferring them to a wire rack to cool completely.

Once the cookies are completely cool, store them in airtight tins or containers.