- 2 cups all purpose flour
- 4 tbsp powdered icing sugar
- 1 cup unsalted butter cold, cubed
- 1-2 tablespoons cold water optional
- 1/2 cup butter unsalted
- 3 cups brown sugar lightly packed
- 4 large eggs
- 2 tbsp white vinegar
- 1 tbsp vanilla
- optional: 3/4 cup raisins
Line a 9×13″ pan and line with parchment paper or spray with non stick. Preheat oven to 350 degrees F.
In a large bowl, combine flour and powdered sugar.
Cut butter into icing sugar and flour with a pastry cutter or your hands until pea-sized lumps of butter remain. When you grab a handful and squeeze, you want it to hold together. If it doesn’t hold together, add 1-2 tablespoons of water.
Dump flour mixture into pan and press down evenly to form a crust. Bake for 10 minutes.
Meanwhile, prepare your filling. In a medium bowl, melt butter in the microwave.
Whisk in brown sugar until smooth. Whisk in eggs, one at a time, then add the vinegar and vanilla. Stir in raisins if using.
Pour over crust and bake another 25-30 minutes until filling is set or almost set — a slight jiggle is fine but you don’t want a lot of movement. Cool to room temperature and refrigerate several hours before slicing.