In a small saucepan, bring the water, sugar, and tea bags to a boil. Simmer for 2 to 3 minutes.
Place the pears upright in the simmering syrup and cook for about 30 minutes over low heat, turning the pears once halfway through.
Pears should be tender with a knife. Allow pears to cool before slicing and placing on top of cake batter.
Pistachio Cake
Preheat oven to 350F and grease a 9-inch cake pan.
In a stand mixer with the paddle attachment, cream together the butter and sugar until mixture becomes light and fluffy. Add in the eggs, one at a time and mix until well-combined. Add vanilla.
In a separate bowl, combine flour, pistachio meal, baking powder, and salt. Whisk together.
In large measuring cup, combine the sour cream and black tea.
Add half the dry ingredients and half of the ingredients in them measuring cup to the butter-sugar mixture. Mix together lightly. Add the remainder of the ingredients and mix until just combined.
Arrange pear slices on top of the batter and sprinkle with raspberries.
Bake cake for 40 - 45 minutes, until a skewer inserted into the middle comes out clean. If the pears and berries are browning too quickly, place a sheet of foil on top while the cake continues to bake.
Once cake is ready, take the cake out of the oven. Allow cake to cool for 30 minutes before glazing. Sprinkle the top of the cake with pistachios.