Wrap the bottom and sides of a 9-inch springform pan with aluminum foil and line the bottom with parchment paper. Spray with non-stick spray.

Combine chilled, cubed unsalted butter with brown sugar, flour, pumpkin pie spice, and pinch of salt in a bowl. Blend until coarse crumbs form, then chill the streusel.

In a bowl, whisk together brown sugar and pumpkin pie spice. Set aside to blend flavors.

Pulse Biscoff cookies in a food processor, then combine with melted butter and sugar in a bowl. Press into the bottom of the springform pan and bake at 350°F for 15 minutes. Cool completely.

Beat cream cheese until smooth. Gradually add sugar and cornstarch, mixing well. Blend in pumpkin purée, sour cream, and spices. Add eggs one at a time, mixing gently.

Pour half the cheesecake batter into the crust, sprinkle the spiced mixture, then add remaining batter. Top with chilled streusel.

Place the pan in a roasting pan and fill the roasting pan with boiling water. Bake at 350°F for 90 minutes. Let cool in the oven for 1 hour.

Cool the cheesecake at room temperature for 30 minutes, then refrigerate for at least 8 hours.

Whip heavy cream with powdered sugar until stiff peaks form right before serving.

Remove cheesecake from the pan and garnish with whipped cream and Biscoff crumbs before serving.