Prepare the Biscoff cookie crust according to this recipe. Press the crust firmly into the bottom and up the sides of an 8-inch deep tart pan (see notes below for pan options). Do not grease the pan before adding the crust.
Bake the crust according to the recipe and set it aside.
In a large bowl, beat the softened cream cheese for one minute. Add the brown sugar and beat until smooth and creamy, about 2–3 minutes.
Add the Biscoff cookie butter and mix to combine.
Add the sour cream and mix until fully combined and smooth, scraping down the sides of the bowl as needed.
Add the eggs one at a time, mixing on low speed just until incorporated after each addition. Along with the second egg, add the vanilla and salt. Mix to combine.
Pour the filling over the prepared crust and smooth the top.
Bake for 40–50 minutes, until the edges are set but the center still has a slight jiggle.
Turn the oven off, crack the oven door open, and leave the pie inside the oven for 20 minutes.
Remove from the oven and let it cool completely at room temperature. Then transfer to the refrigerator and chill for at least 6 hours, or overnight, until fully set.
Before serving, pour about ½ cup of melted Biscoff cookie butter over the top and sprinkle with Biscoff cookie crumbs.
Notes
I used an 8-inch deep tart pan, but you can also use a 9-inch tart pan or a springform pan.Sour cream: You can use full-fat yogurt instead of sour cream.Brown sugar: Granulated sugar can be used instead.Biscoff butter: I used creamy butter. Feel free to use creamy or crunchy.Cream cheese: Use the block kind, not the spreadable type.