Cream butter and sugar in a large bowl with a mixer. Add eggs, vanilla and pickle juice, and mix until combined. Add flour, baking powder and salt. Mix until smooth. Fold in sour cream and chopped pickles.
Add batter to lined cupcake tins, filling them three-quarters of the way. Bake 20 to 25 minutes or until a toothpick comes out clean.
Top with vanilla frosting and garnish with dill pickles.