Preheat oven to 350 degrees and line cupcake tin with cupcake liners.
In the bowl of a stand mixer, beat together butter and sugar until light and fluffy. Beat in eggs one at a time, scraping down the sides of the bowl after adding each egg. Beat in vanilla.
In another bowl combine flour, baking powder and salt.
Slowly add in 1/3 of the dry mixture. Then add in 1/3 of the milk. Repeat alternating until all ingredients have been added. Fold in chocolate chips.
Fill cupcake liners 2/3 of the way full (about 1/4 cup of mixture). Bake for 15 - 20 minutes or until a toothpick inserted comes out clean. Remove from oven, allow to cool several minutes then transfer to a cooling rack to cool completely.
Meanwhile make frosting by beating together butter and sugar until fluffy. Beat in vanilla extract. Beat in 2 tablespoons milk until a stiff spreadable mixture forms. If too stiff, add remaining milk.
Use a small knife to gently slice down the middle of the vanilla bean and scrape the insides into the frosting. Continue mixing just until combined.
Place frosting in a piping bag and pipe onto cupcakes. Serve.
If you refrigerate the cupcakes, take them out about an hour before serving.