Heat oven to 350F. Add the butter and chocolate chips to a saucepan set over medium heat. Cook, stirring frequently, until melted. Stir in the rum and let cool. Beat in eggs one at a time.

Add flour, sugar, cinnamon, chipotle powder, baking powder, baking soda, and salt to a mixing bowl. Stir well, breaking up any clumps of brown sugar that might have formed. Stir in half the chocolate. Mix well. Stir in remaining chocolate and mix until combined. Pour into a greased loaf pan.

Bake 40-55 minutes, or until the center of the cake is set and a knife inserted into the middle comes out clean. Remove from oven. If using the additional rum, use a knife or skewer to poke several holes throughout the cake; pour remaining 1/4 cup of rum over cake. Let cool until rum is completely soaked in. Invert onto a plate and remove the pan.

Add the pears and sugar to a saute pan. Cook, stirring frequently for 5 minutes or until pears or slightly softened and sugar is golden brown. Spoon pears over cake.