Preheat oven to 425* F and line a baking tray with parchment.
Into a mixing bowl, add flour, sugar, baking powder, baking soda and salt. Mix to combine.
Add the cubed non-dairy butter and work the butter into the dry ingredients with your hands. Work the butter in until is just smaller than small peas.
Remove the earl grey tea from the refrigerator. Measure 6 tablespoons of the earl grey tea to add to the butter and flour mixture. If you don't have enough, supplement with nondairy milk. Then, add the vanilla and vinegar.
Toss everything together with your until the mixture is moist. It will be very dry at first but it will come together.
Pour the mixture onto a work surface and fold it onto itself a few times until the dough becomes cohesive. This will be about 3 folds. See note.
Press the dough into a circle that is about 6-7 inches in diameter and 1 inch tall.
Cut the dough round into 6 triangles.
Transfer the triangles to a parchment-lined baking sheet and bake on the middle rack of a 425* F oven for 15-17 minutes or until the bottoms of the scones are browned all the way across.
Remove from the oven and allow to cool for 10 minutes before glazing.