**Prepare the Crust:**
- Preheat your oven to 325°F (160°C). Grease a 9-inch springform pan and line the bottom with parchment paper.
- In a medium bowl, combine the graham cracker crumbs, melted butter, sugar, and salt. Mix until the crumbs are evenly moistened.
- Press the mixture firmly into the bottom of the prepared pan to form an even layer. Bake the crust for 10 minutes, then set aside to cool.
**Prepare the Cheesecake Filling:**
- In a large bowl, beat the cream cheese and brown sugar together until smooth and creamy. Add the eggs, one at a time, beating well after each addition. Stir in the vanilla extract.
- Slowly mix in the heavy cream until fully incorporated, then add the melted butterscotch chips, mixing until smooth.
- Pour the cheesecake filling over the cooled crust, smoothing the top with a spatula.
**Prepare the Buttery Crumble Topping:**
- In a medium bowl, combine the flour, brown sugar, and salt. Add the cold, cubed butter and use a pastry cutter or your fingers to mix until the mixture resembles coarse crumbs.
- Sprinkle the crumble topping evenly over the cheesecake filling.
**Bake the Cheesecake:**
- Place the springform pan on a baking sheet and bake the cheesecake for 50-60 minutes, or until the center is set and the crumble topping is golden brown.
- Turn off the oven and let the cheesecake cool inside with the door slightly open for 1 hour.
- Remove the cheesecake from the oven and let it cool to room temperature. Refrigerate for at least 4 hours, preferably overnight, before serving.
**Serve:**
- Once chilled, remove the cheesecake from the springform pan and place it on a serving plate. Slice and serve, enjoying the rich, creamy butterscotch flavor with every bite.