Line a 12-cup muffin pan with paper liners and set aside.
In a bowl, combine the crushed Biscoff cookies and melted butter and stir until all crumbs are evenly coated and the mixture feels like damp sand.
Divide the crumb mixture evenly among the 12 liners and press firmly into the bottoms using the back of a spoon or a flat-bottomed glass to form compact crusts.
Place the pan in the refrigerator to chill the crusts while you prepare the cheesecake filling.
Preheat the oven to 285°F (140°C).
In a large mixing bowl or stand mixer bowl, add the room-temperature cream cheese and sour cream and beat on medium speed until completely smooth and no lumps remain.
Add the 150 ml melted Biscoff spread, brown sugar, and speculoos spice and mix on low speed just until fully combined.
Add the eggs one at a time, mixing on low speed after each addition only until just incorporated to avoid adding excess air to the batter.
Remove the pan from the refrigerator and divide the cheesecake batter evenly over the chilled crusts, filling each liner almost to the top.
Tap the pan gently on the counter a few times to release any air bubbles from the batter surface.
Bake for 18 to 20 minutes, or until the edges are set and the centers still have a slight jiggle when the pan is gently shaken.
Remove the pan from the oven and let the cheesecakes cool completely in the pan at room temperature.
Once cooled, transfer the pan to the refrigerator and chill the cheesecakes for at least 2 hours, or until fully set.
For the glaze, melt the 80 ml Biscoff spread until fluid and warm, then let it cool slightly so it is still pourable but not hot.
If desired, carefully remove the paper liners from the chilled cheesecakes, then place the cheesecakes on a tray.
Spoon or pour a little of the melted Biscoff spread glaze over the top of each cheesecake, tilting gently if needed to fully cover the surface.
Return the glazed cheesecakes to the refrigerator and chill until the glaze is set.
For the Biscoff whipped cream, melt the 45 ml Biscoff spread until fluid, then set aside to cool to just warm or room temperature.
In a large chilled mixing bowl, add the cold heavy cream and begin whipping on medium speed until it slightly thickens.
With the mixer running on medium speed, slowly pour in the cooled melted Biscoff spread and continue whipping until stiff peaks form.
Transfer the Biscoff whipped cream to a piping bag fitted with a star or round tip, or keep it in the bowl to spoon on.
Just before serving, pipe or spoon a generous swirl of Biscoff whipped cream onto each chilled, glazed mini cheesecake.
Garnish each cheesecake with a half Biscoff cookie, pressing it gently into the whipped cream.
Keep the mini Biscoff cheesecakes refrigerated until serving and store any leftovers covered in the refrigerator.