Preheat the oven to 350.

Add butter and sugar to a large bowl and beat until creamy. Add the zest and beat together until the butter and sugar mixture is light and fluffy, about 2-3 minutes. Add eggs, one at a time, incorporating well before adding the next.

In a separate bowl, combine flour, baking powder, and salt. Mix to combine. In a measuring cup, add the milk, clementine juice, and vanilla. You should end up with 1 cup of liquid total.

Add the dry ingredients in 3 additions, alternating with the wet ingredients, and lightly beating in between each addition. Begin and end with the dry mixture. Do not overbeat.

Place cupcake liners into a standard cupcake pan. Fill cupcake cups evenly about 3/4’s full. Bake cupcakes for about 17-20 minutes or until a toothpick comes out clean. Do not overbake. Remove cupcakes from the pan and cool on a rack, for at least 30 minutes.

To make the frosting, cream softened butter and cream cheese together on medium speed until smooth. Add 2 cups of confectioners sugar and beat on low speed until sugar is all incorporated. Add vanilla extract, zest, and juice. Add 1-2 more cups sugar and mix on low speed until sugar is all incorporated. If you want a smoother consistency, add a splash of milk or more clementine juice. Frost cooled cupcakes with a butter knife, or pipe them with a piping bag, and place a clementine segment on top of each cupcake.