Spiced Harwich Hermits

2 cups flour
1 teaspoon baking powder
1/2 teaspoon baking soda
1/2 teaspoon salt
3/4 teaspoon ground cinnamon
1/2 teaspoon nutmeg, grated
1/4 teaspoon ground mace
1/4 teaspoon ground cloves
1/4 lb unsalted butter, softened (1 stick)
1/2 cup sugar
2 eggs
1/3 cup molasses
1 cup raisins, coarsely chopped
1/2 cup walnuts, chopped

Preheat the oven to 350°F.
Grease a 15x10 inch jelly roll pan.
Whisk together the flour, baking powder, baking soda, salt, cinnamon, nutmeg, mace, and cloves in a mixing bowl.
Using an electric mixer, cream the butter with the sugar in a large bowl until smooth and fluffy.
Beat in the eggs and molasses until well blended.
With the mixer on low speed, add the flour mixture, beating just until blended.
Stir in the raisins and nuts.
Scrape the batter into the prepared pan, spreading it out evenly to the edges and smoothing the top.
Bake until firm on the top and a tester inserted in the center comes out clean, 15 to 18 minutes.
Cool in the pan on a rack for 10 minutes, and cut into 1 1/2 by 2 1/2 inch squares.
Store the hermits in a tightly covered container for up to a week or so.