Bring water to a boil in a medium pot. Reduce to a simmer and add the tea bags. Allow the tea to steep for 10 minutes. Remove the tea bags and add the sugar.
Once the sugar is dissolved, add the pears and bring back up to a boil. Then, reduce to a simmer and allow the pears to simmer for 20 minutes, beginning to check their doneness at the 15-minute mark. Pears will be fork tender when done. Carefully remove them from the pot and allow them to drain on a paper towel-lined plate. Set aside as you mix the cake.
Preheat oven to 350° F.
Grease a loaf pan with butter or non-stick spray. Line the pan with parchment paper.
In a large bowl, add the flour, cocoa powder, baking soda, and salt, and mix to combine.
In another bowl, beat the butter until light and fluffy, about 5 minutes. Add brown sugar and mix to combine. Add eggs one at a time.
Add half the flour mixture. Then, add the milk and sour cream, and beat again until fully combined. Add remaining flour mixture. Using a wooden spoon, mix until just combined.
Line the bottom of the pan with a quarter cup of the batter. Place the pears, standing upright in the pan, an even distance apart.
Carefully pour the remaining batter around the pears.
Bake for 50 minutes. Remove from the oven and allow to cool completely in the pan.
Remove from tin. Pour ganache (instructions below) on top. Slice and serve.
