Preheat oven to 350 F. Line 2 mini cupcake pans ( 2-inch diameter) with paper liners.
Place sugar & zest in the mixer bowl & blend until moist & fragrant. Add butter & beat until white. Add eggs, one at a time; beating well after each one.
In a separate bowl, combine flour, salt & baking powder. With mixer on low speed, add the flour, milk & liqueur alternately, scraping down sides of the bowl. Divide cake batter between the 24 paper lined cups.
Bake 16-18 minutes, or until risen & baked through, testing with a toothpick in the center of the cupcake. Remove from baking pan & allow to cool.
Frosting
Combine butter & cream cheese with a mixer until smooth & creamy. Blend in Benedictine liqueur. Slowly add the powdered sugar until you reach the right consistency. If you are using a pastry bag ensure that you have a medium consistency.
Pipe the frosting onto each cupcake then garnish as you wish.