1 cup butter
3/4 cup molasses
4 cups flour
2 1/2 tsp cinnamon
2 1/2 tsp ground cloves
1 tsp ground ginger
1/4 tsp salt
2 tsp baking soda
1/4 cup brewed orange-pekoe tea
6 cups partridgeberries, also known as lingonberries (or substitute cranberries)
2 tbsp lemon juice
1 tbsp lemon zest
1/2 cup brown sugar
To make the pastry dough, cream the butter and molasses. In a separate bowl, sift together the flour, cinnamon, cloves, ginger and salt. In a small bowl or cup, stir the baking soda into the hot brewed tea, then add immediately to the butter-and-molasses mixture and stir well. Add dry ingredients to the same bowl and mix until just combined. Pat the dough into a ball and flatten, wrap in plastic wrap and chill it in the fridge overnight or for at least 2 hours.
To make the partridgeberry jam, place the berries, lemon juice, lemon zest and sugar in a heavy-bottomed pot and simmer over medium-low heat for 1 hour. Set aside and let cool.
To assemble the tarts, roll out the dough to 1/8 inch thick and 10 inches round. Transfer to an 8-inch tart pan and trim the overhanging edges. Form a ball with the scraps, roll out the dough and cut out strips for the lattice top.
Fill tart with 1/2 inch of partridgeberry jam. Place the lattice overtop and use a fork to crimp the edges of the pastry.
Bake at 325 F for 35 minutes or until the top is dark brown.