Step 1: Place a large mixing bowl and your whisk attachments in the freezer for 5 minutes to chill.
Step 2: Pour the 1 cup of heavy whipping cream into the chilled bowl and whip on medium-high speed until stiff peaks form.
Step 3: Place the 1 cup of Biscoff spread in a microwave-safe bowl and heat for 15 seconds until it is slightly softened and easy to stir.
Step 4: Add one large spoonful of the whipped cream into the Biscoff spread and stir until well combined and lightened.
Step 5: Gently fold the Biscoff mixture back into the main bowl of whipped cream using a spatula until the color is uniform and no white streaks remain.
Step 6: Spoon the mousse into serving dishes and refrigerate for at least 30 minutes before serving.