In a small bowl, combine the graham cracker crumbs, sugar, melted butter, and vanilla extract. Stir until the mixture is evenly moistened.

Press the mixture firmly into the bottom of an 8- or 9-inch square pan or glass pie plate to form an even layer.

Refrigerate for at least 20 minutes to set while preparing the filling.

In a large bowl, beat the softened cream cheese and both sugars using a hand or stand mixer. Scrape down the sides of the bowl as needed, and continue mixing until smooth and creamy with no lumps.

Add the vanilla extract and lemon juice, and mix until just combined.

Gradually pour in the heavy cream in 3-4 increments, whipping it into the cream cheese mixture after each addition until fully incorporated and the filling is light and fluffy.

Fold in the pumpkin purée and ground cinnamon with a spatula.

Pour the cheesecake filling over the prepared crust, spreading it out evenly.

Cover the pan with plastic wrap and refrigerate for at least 8-10 hours, or until the cheesecake is fully set and chilled.

Before serving, loosen the edges of the cheesecake with a knife.

Slice and wipe the knife clean after each cut for neat slices.

Optionally, sprinkle crushed Biscoff over the top for extra texture and flavor.