- With the rack in the middle position, preheat the oven to 350°F (180°C). Butter and line an 8-inch (20 cm) square baking pan with parchment paper, letting it hang over two sides.
- In a bowl, combine the cookie crumbs and butter. Press lightly into the bottom of the prepared pan. Bake for 12 minutes. Let cool. Reduce the oven temperature to 325°F (165°C).
- In a food processor, combine the cream cheese and brown sugar. Add the sour cream and eggs. Purée until just smooth. With a spatula, scrape the bottom and sides several times. Set aside.
- In another bowl, combine the pumpkin purée with the cinnamon and ½ cup (125 ml) of the cream cheese mixture. Set aside.
- Spread the plain cream-cheese mixture over the crust. Pour the pumpkin cream-cheese mixture onto the cheese filling in 4 parallel lines. Run the tip of a knife through the pumpkin mixture in opposite directions, 6 to 8 times, to form a marbled effect.
- Prepare a hot water bath: Place the pan in a baking dish and pour boiling water into the dish to reach one-third up the pan.
- Bake for 30 to 35 minutes or until the centre of the cheesecake is set but still soft. Remove the pan from the hot water bath. Let cool for 1 hour. Freeze at this stage, if desired. Otherwise, cover with plastic wrap and refrigerate for 4 hours or overnight.
- Run the blade of knife between the pan and the cheesecake. Carefully remove the cake using the parchment paper. Place on a work surface and cut into 12 squares.