Preheat the oven to 350 degrees F. Line 12 large or 48 mini cupcake cups with paper liners. Cream the butter and sugar with an electric mixer until light and fluffy, about 3-5 minutes on high. Then add the chai latte powder and extra cardamom if desired.
Mix in the eggs, milk, and vanilla. Scrape the bowl with a spatula. Then mix the baking powder and salt with the flour and add to the wet mixture a little at a time.
Fill the liners 2/3 of the way full and bake: 10 minutes for minis, and 15-20 minutes for regular cupcakes. Check by inserting a toothpick into the center of a cupcake. If it comes out clean, they are done!
Once the cupcakes have cooled, make the frosting. Cream the butter and sugar together, with an electric mixer, until light and fluffy, 3-5 minutes. Add the rest of the ingredients and beat until smooth. If the frosting is too soft add 1/2 cup more powdered sugar. Pipe the frosting on each cupcake and enjoy!