2pureed kiwisbe sure to remove the white center from the kiwis, or puree them really good. The white part can clog up your piping bag if it isn’t pureed well.
Preheat the oven to 350 degrees F.
In a small bowl combine the flour, baking powder, baking soda, salt and sugar. Whisk and set aside.
In a mixing bowl combine the eggs, melted butter, vanilla, and sour cream until combined.
Slowly add half of the flour mixture to the liquid, stirring to combine. Repeat with the rest of the flour mixture.
Divide the batter among a muffin pan lined with muffin liners, fill the muffin cups to be about a little more than 1/2 full.
Bake for 14-16 minutes or until a tooth pick inserted in the center comes out clean.
In a mixing bowl, combine the room temperature butter and shortening, beat using an electric mixer for 2 minutes, until light and fluffy.
Add in the pureed kiwi and mix until combined. If you see kiwi chunks in your puree, remove them as this time.
Begin to add in the powdered sugar, about 1 cup at a time. Slowly beat the mixture until the powered sugar is incorporated. Continue this process, adding enough powdered sugar to make sure the frosting isn’t too wet.
Transfer a portion of the frosting to a large ziploc bag or piping bag. Push or squeeze the frosting down, getting rid of any air pockets. If using a ziploc bag, cut half one corner, making a hole between the size of a dime and a penny.
Begin to pipe the frosting onto a cupcake, starting with the outside edge and working your way into the center of the cupcake, progressively stacking the frosting as you go around in circles.