Directions

1. Preheat oven to 350°F (176ºC). Line a 9 inch cake pan pan with parchment paper so that it covers the bottom and goes up the sides of the pan. Fold parchment paper so that it hugs the sides of the pan, like an upside down hat. Spray with non-stick spray.
2. With a sharp paring knife, slice ends of oranges and grapefruit. Following curve of fruit, cut away peel, removing as much white pith as possible. Slice oranges and grapefruit crosswise into 1/4-inch-thick rounds and remove any seeds; set aside. Slice kumquats into 1/4-inch-thick rounds and remove any seeds; set aside.
3. Attach Sifter Attachment (without Sifter Assembly) to KA Stand Mixer (with Whisk Attachment), and press "Tare" to zero scale. Add brown sugar to ingredient hopper and weigh. Add brown sugar into Stand Mixer bowl through chute.