Prepare a 8 x 8-inch pan with baking paper and cooking spray. Preheat your oven to 170c. Crush your crackers until fine like breadcrumbs, don't be concerned about bigger chunks among the crumbs. Add your melted butter and brown sugar. Mix well and press into prepared pan, place in the fridge for 15 minutes.
Beat cream cheese on a medium speed until smooth. Add sugar and vanilla and beat until combined. Add in eggs one at a time until combined. Spread over prepared base and place in the oven for 25 minutes.
Roughly chop pecans and add in brown sugar and butter. Mix well. After the cheesecake has baked for 20 minutes, remove and gently top with the pecan mixture. Spreading over gently, but firmly pressing into the cheesecake. By placing this on top after some baking time, it ensures the pecan mixture doesn't settle to the bottom and doesn't burn. Place back in the oven for 15 more minutes.
Allow to cool completely, then place in the fridge for a couple hours to chill. It is easiest to cut these when it is chilled. Remove and slice into squares. if you feel you may break the cheesecake when removing, then slice them first and remove one slice at a time. Store in the fridge until ready to serve.
Variation: For this recipe I used salty crackers and salted butter. You could use unsalted butter and biscuits instead if you don't like salty sweet desserts. If using sweet biscuits, there'll be no need for the brown sugar in the base.