Heat the milk until just boiling, either on the stove in a small saucepan or in the microwave. Steep teabags in milk for about 5 minutes.

Whisk together flour, salt, and baking powder.

With a mixer, cream butter and sugar on medium speed for about 2-3 minutes, or until fluffy and well combined.

Reduce speed to low, and add egg, then egg white, letting mix until well combined after each addition. Add in vanilla extract.

Add about 1/3 of the flour mixture, then about 1/2 of the tea infused milk. Beat until just combined, scraping the sides of the bowl if necessary. Repeat with another 1/3 of the flour and the rest of the milk. Add in the remaining flour. Turn speed to medium and mix until all flour is incorporated, about 1 minute.

Divide batter evenly into muffin cups, spooning each cup about 3/4 full.

Bake for 20-25 minutes, or until skewer inserted into the middle of a cupcake comes out clean.

Remove from the muffin tin and allow to cool on a cooling rack.

Add sugar, water, and tea bags to a small saucepan. Bring to a simmer, and once simmering allow tea bags to steep for 5-8 minutes. The longer you steep the tea, the stronger the earl grey flavor will be. Set aside and allow to cool.

In a standing mixer, cream butter until smooth. Add Irish cream, and stir for 1-2 minutes on medium-low speed.

Slowly add in powder sugar, one cup at a time, until frosting is smooth and sugar is well incorporated. It's helpful to use a spill guard or clean kitchen towel to prevent sugar from getting all over your kitchen when mixing in the sugar!

Brush each cupcake with simple syrup, doing about 2-3 coats of syrup per cupcake. Frost cupcakes with buttercream, and enjoy!