1. Generously coat six 6-ounce ramekins with softened butter.
2. Chill in the freezer for about 10 minutes, and brush with a second coat of butter.
3. Pour 3 tablespoons caramel sauce into the bottom of each ramekin and transfer to the freezer for 1 hour.
4. Whisk the cake flour, cocoa, baking soda, sugar, and salt together in a large bowl and set aside.
5. Stir the tea, oil, vanilla, and vinegar together and whisk into the flour mixture just until smooth.
6. Fill each ramekin with 1/3 cup of batter.
7. Bake at 400F until the cake is set and a toothpick inserted in the center comes out clean, and the caramel has bubbled up against the sides, about 20 minutes.
8. Garnish with extra caramel sauce and whipped cream, optional.