Preheat oven to 350F/175C. Line an 8x8 pan with parchment, folding it over at least two the edges (feel free to trim as you like).

Make your shortbread by whisking the flour and salt together. Be sure your flour was spooned and leveled into the measuring cup then sifted. Set aside.

Beat the butter and peanut butter on high until smooth. Add powdered sugar and beat on low then increase to high until very smooth, about 1 minute. Add vanilla and beat until smooth.

Add flour and beat on low just until combined.

Press about ⅔ to ¾ of the dough into your prepared pan. Optionally, you can freeze the dough for 10 minutes or refrigerate for 20 minutes. You can chill it longer, but be sure to cover it so it doesn’t absorb any smells from your fridge.

After freezing, bake for about 10 minutes, until puffy and matte in appearance, with the edges just beginning to show some golden color.

Let cool for a few minutes, then gently spoon your jam over the baked shortbread, gently spreading it to the very edges. Avoid pressing too firmly to keep the bottom layer intact.

Sprinkle the remaining dough on top. Feel free to cover the jam or to leave some gaps. Optionally, you can add some chopped peanuts as well.

Bake for 10-12 minutes more, until the top is matte and slightly golden. Let cool for at least 30 minutes before lifting the parchment and slicing.

Enjoy! Cover leftovers and keep at room temperature for up to 1 week.