Place tea bags in a glass measuring cup; pour boiling water over tea bags. Let steep for 8 minutes. Remove and throw away tea bags; cool tea completely.
4 Earl Grey tea bags, 1/3 cup boiling water
Preheat oven to 300 °F .
In a medium bowl, combine flour, baking powder, salt, and cocoa; set aside.
2 cups all-purpose flour, 1/2 tsp. baking powder, 1/2 tsp. table salt, 1/3 cup unsweetened cocoa
Beat butter at medium speed with a mixer (hand or stand) for 2 minutes. Gradually add sugar, beating 5 minutes more. Add eggs one at a time, beating just until yellow disappears.
1 cup (2 sticks) butter, softened, 2 cups granulated sugar, 4 large eggs
Stir together milk and tea. Add flour mixture to butter mixture alternately with milk mixture, beginning and ending with flour mixture. Mix at low speed after each addition, just until blended. Stir in vanilla.
1/3 cup whole milk, 1 tsp. vanilla extract
Pour batter into a greased and floured 10-cup Bundt pan. Bake for 1 hour and 15 minutes or until a toothpick comes out clean. Cool cake in pan on a wire rack 10 to 15 minutes; remove from pan and cool cake completely on wire rack. Dust with confectioners' sugar and serve with chocolate sauce (instructions to follow).
confectioners' sugar for dusting