Cupcakes
Preheat oven to 350°F. Butter or spray with nonstick cooking spray (or line with cupcake wrappers) cups of 2 cupcake or muffin pans.
In medium mixing bowl, sift together flour, baking powder, baking soda and salt. In an electric mixer bowl, cream butter with sugar at medium speed until light and fluffy. Add vanilla, lemon zest, lemon juice, ginger and eggs and beat again until fully blended.
Add 1/2 of the flour mixture to the butter, sugar and egg mixture and mix on low speed until blended. Add buttermilk and mix again until blended. Add remaining flour and mix on low speed just until blended, stopping once to scrape sides and bottom of bowl to incorporate all ingredients.
Pour batter into muffin cups to about 2/3 full. Bake for 17-20 minutes, or until a toothpick inserted into center of one of the cupcakes comes out clean. Remove from oven and allow cupcakes to cool in the muffin cups for 5 minutes, then transfer to a wire rack to completely cool.
Once completely cooled, spread cupcakes with cream cheese frosting (recipe follows).
Cream Cheese Frosting
In an electric mixer bowl (alternatively, an eletric hand mixer can be used), blend the butter and cream cheese on medium high speed until thoroughly blended. Add the powdered sugar and blend on low speed until sugar is fully blended into the cream cheese and butter mixture, then increase speed to medium and beat until smooth and creamy (about 15-30 seconds). Blend in the vanilla extract, lemon juice and lemon zest (if using) and beat again just until blended.
Apply frosting to cooled cupcakes.
(Note: If frosting is too runny, additional powdered sugar can be blended into the frosting (2 tablespoons at a time), or frosting can be refrigerated for about 30 minutes to help it thicken).