Reduce oven temperature to 300°F.
In a large bowl, on low speed, beat the cream cheese, sugar and flour until completely combined and smooth; be sure to use low speed to reduce the amount of air added to the batter which can cause cracks; scrape down the sides of the bowl.
Add the sour cream, peanut butter and vanilla extract; mix on low speed until well combined.
Add the eggs, one at a time, mixing slowly to combine after each addition; scrape down the sides of the bowl, as needed, to make sure everything is well combined.
Stir in the chopped Butterfingers.
Pour the cheesecake batter evenly into the crust.
Place the springform pan inside another larger pan; fill the outside pan with enough warm water to go about halfway up the sides of the springform pan; the water should not go above the top edge of the aluminum foil on the springform pan.
Place in the pre-heated oven and bake for 1 hour 25 minutes; the center should be set, but still jiggly.
Turn off the oven and leave the door closed for 30 minutes; the cheesecake will continue to cook, but slowly begin to cool as well.
Crack the door of the oven for 30 minutes to allow the cheesecake to continue to cool slowly; this process helps prevent cracking.
Remove the cheesecake from the oven and water bath wrapping; refrigerate until firm; 5 - 6 hours or overnight.
When the cheesecake is cool and firm, remove from the springform pan and set on a serving plate.