01 - Preheat oven to 325°F. Grease a 9-inch springform pan and line bottom with parchment paper.
02 - Combine graham cracker crumbs, granulated sugar, pinch of salt, and melted butter in a bowl. Press mixture firmly into prepared pan base. Bake for 10 minutes, then allow to cool completely.
03 - In a large mixing bowl, beat cream cheese until perfectly smooth. Blend in granulated sugar and vanilla extract until homogeneous.
04 - Add eggs sequentially, mixing just until incorporated after each addition. Gently blend in sour cream and flour, ensuring batter remains smooth without overbeating.
05 - Divide mixture evenly into three bowls. Leave one portion plain. Tint the second bowl with red gel food coloring and the third with blue gel food coloring, adjusting intensity as desired.
06 - Spoon alternating amounts of each colored batter onto the cooled crust to achieve a patchwork arrangement. Gently swirl with a skewer or knife for a marbled appearance, avoiding excessive mixing.
07 - Bake for 50 to 60 minutes, until center is set yet still retains a gentle jiggle. Turn off oven, crack oven door, and allow cheesecake to cool inside for 1 hour.
08 - Remove cheesecake from oven and refrigerate for at least 3 hours before slicing for clean portions.