Preheat oven to 350ºF. Prepare muffin pans with baking cups.
In large bowl, sift together flour, baking powder, ginger and salt.
In large bowl, beat butter and sugar with electric mixer until light and fluffy. Add vanilla and half of chopped crystallized ginger; mix well. Add eggs, one at a time, beating well after each addition. Add flour mixture alternately with ginger ale;until just combined. Divide batter evenly into baking cups, filling about 2/3 full.
Bake 18-20 minutes or until toothpick inserted into center of cupcake comes out clean. Cool cupcakes in pan on cooling grid 5 minutes. Poke tops of cakes gently with a fork; brush with whiskey. Remove from pan; cool completely on cooling grid.
Whiskey Buttercream
In large bowl, beat butter, vanilla and salt with electric mixer until smooth and creamy. Gradually add confectioners' sugar, 1 cup at a time, beating well after each addition. Gradually add whiskey, beating until fully incorporated. Beat on medium-high speed 2 minutes or until very smooth and fluffy.
Ice cupcakes with whiskey buttercream and sprinkle with remaining half of crystallized ginger.