In bowl fitted for your stand mixer, bring the two eight ounce bricks of cream cheese to room temperature.
Prepare a 6" springform pan by clipping a sheet of parchment paper into the base and trim to fit. Place two large squares of aluminum foil on a flat surface. Set the springform pan in the middle of the foil. Gently fold up the sides of the foil around the pan and crimp the edges, being careful not to rip the foil. This will keep the water bath from seeping into the cheesecake.
Spray the inside of the springform pan with cooking spray, and line the sides with parchment paper. Set prepared springform pan inside a larger cake pan, which will hold water during baking.
Pre-heat oven to 350 degrees, and set rack to the bottom third of the oven.
Start a small pot with water to boil for the water bath.
Chop and saute approximately two leek whites, 1/4 cup when cooked.
Add sauteed leeks and remaining ingredients to the mixing bowl, and mix on medium speed until smooth, scraping down the sides of the bowl.
Pour the cheesecake mixture into the prepared springform pan. Place the nesting pans in the oven, and fill the outside cake pan with boiling water.
Bake the cheesecake for one hour. Remove from oven, remove the foil, and bring to room temperature. Chill completely before removing the springform pan and the parchment paper.