Step 1: Preheat your oven to 325°F (160°C). Wrap the bottom and sides of a 9-inch springform pan tightly with heavy-duty aluminum foil to prevent water from seeping in during the water bath.
Step 2: For the crust, combine the finely crushed sugar cookies and melted butter in a medium bowl. Press the mixture firmly into the bottom of the prepared springform pan. Bake for 10 minutes. Remove from oven and let cool slightly.
Step 3: In a large bowl, using an electric mixer, beat the softened cream cheese on medium speed until smooth and creamy, about 2-3 minutes. Scrape down the sides of the bowl.
Step 4: Gradually add the granulated sugar and flour to the cream cheese, beating until just combined and smooth. Do not overmix.
Step 5: Beat in the vanilla extract and almond extract. Add the eggs one at a time, beating on low speed until just incorporated after each addition. Mix in the sour cream until combined.
Step 6: Pour the cheesecake filling over the cooled sugar cookie crust in the springform pan. Place the springform pan into a larger roasting pan.
Step 7: Carefully pour hot water into the roasting pan, around the springform pan, until it reaches about halfway up the sides of the springform pan.
Step 8: Bake for 1 hour 15 minutes to 1 hour 30 minutes, or until the edges are set but the center still jiggles slightly when gently shaken. The internal temperature should be around 150°F (65°C).
Step 9: Turn off the oven, crack the oven door open, and let the cheesecake cool in the water bath inside the oven for 1 hour. This slow cooling helps prevent cracks.
Step 10: Carefully remove the cheesecake from the water bath and the roasting pan. Remove the foil. Let it cool completely on a wire rack at room temperature.
Step 11: Once completely cool, cover the cheesecake with plastic wrap and refrigerate for at least 6 hours, or preferably overnight, to allow it to set fully.
Step 12: Before serving, prepare the whipped cream topping: In a cold bowl, beat the heavy whipping cream and powdered sugar on high speed until stiff peaks form.
Step 13: Spread the whipped cream over the top of the chilled cheesecake. Decorate with festive Christmas sprinkles and miniature sugar cookies as desired. Slice and serve cold.