Preheat oven to 350°F.

line an 8 inch square baking pan with an 8x13 sheet of parchment , letting it hang over.

using a food processor, pulse peanuts until chopped. Transfer to a medium bowl.

in the processor bowl, mix the two flours, brown sugar and salt. Add the butter; pulse until the mixture resembles course meal. Add peanut butter and vanilla; process until crumbly. Measure out 2/3 cup of the crumb mixture; transfer to the bowl of peanuts.

Dump the remaining crumb mixture into the prepared pan and pat down firmly. Spoon the jam on top and spread to within 1/2 inch of the edges. Sprinkle the peanut-crumb mixture evenly over top, going all the way to the edges of the pan.

Bake until the top is golden brown and the jam is bubbling' about 45 minutes. (if browning too quickly on top, lay a sheet of foil loosely over the pan.) Transfer the pan to a rack and cool completely.