Pour the milk into a heavy-bottomed saucepan with a tight fitting lid. Scald the milk (heat until it is steaming and many tiny bubbles have formed in the milk around the edge of the pan. Add the tea bags, remove the pan from the heat and put the lid in place. Let the milk cool to room temperature like this. When the milk is cool, squeeze the excess liquid from the tea bags and discard them. Measure one cup plus 2 tablespoons of the cooled infused milk and reserve the rest.
Preheat oven to 375°F.
In a stand mixer fitted with the paddle attachment (or a mixing bowl with an electric hand-held mixer) beat together the butter and sugar until lighter in colour and fluffy.
Add the eggs, one at a time, beating well after each addition and scraping down the bowl. Add the vanilla extract and beat well.
In a separate bowl, whisk together the flour, baking powder and salt.
Add about 1/3 of the flour mixture to the butter/egg/sugar. Beat on low just until combined. Add about 1/3 of the infused milk that you measured. Again, beat just until combined, scrape down the sides of the mixing bowl and repeat -flour, milk, flour, milk- until both flour and milk are completely incorporated.
Line 24 muffin/cupcake wells with cupcake liners and spray lightly with non-stick cooking spray. Fill the liners about 2/3 full of cupcake batter.
Bake for 18-22 minutes, or until they spring back when pressed lightly or a toothpick inserted into the center of a cupcake comes out clean.
Let the cupcakes cool in the pan for 5 minutes before turning out onto a cooling rack to finish cooling completely.