Cut pears in half lengthwise. Use a melon baller, remove the seeds and core. Brush the pears with orange juice and place on the grill cut side down. Let the pears cook until they are lightly caramelized, about 5 minutes.
Cream butter and sugar together in a large bowl. Beat in egg and molasses. In a separate bowl, combine dry ingredients and whisk until mixed. Add 1/3 of the dry ingredients to the creamed mixture and mix. Add 1/3 of the hot water and mix. Continue alternating dry ingredients and water in thirds until all is incorporated.
Pour the batter into prepared pans and bake for 45 minutes or until a toothpick inserted in the middle comes out clean.