Preheat the oven to 325 degrees. Spray a 13X9-inch baking dish with nonstick cooking spray.
Add the graham crackers crumbs and the melted butter into a bowl. Stir to combine.
Press the mixture into the bottom of a baking dish and bake for 10 minutes. Let it cool entirely.
Beat the cream cheese and sugar with a mixer until smooth.
Mix in the vanilla, sour cream, and flour and combine well.
Beat in the eggs one at a time.
Separate the mixture into three bowls evenly. Add red food coloring to one, blue to the other, and leave the last as is. Stir all the bowls with color.
Add the mixture to the pan, alternating the colors.
Use a knife and swirl the mixture by dragging it down the length of the pan. Go short ways up and down.
Put the pan in the oven and bake for 45-50 minutes.
Let it cool for one hour on a wire rack, and then put it into the fridge for 4-6 hours to cool before cutting and serving.