- 1. Sift together the flour, baking soda, and salt. Place the brown sugar in a food processor and process until the sugar is very fine, about a minute. Add the butter and peanut butter and process until creamy, about 10 more seconds. With the motor running, add the egg yolk and vanilla and process until incorporated. Scrape down the bowl; then add the flour mixture and pulse to combine. Wrap the dough in plastic and refrigerate for at least 1 hour.
- 2. Once chilled, roll out the dough between two sheets of parchment paper to make a circle about 1/8 inch thick. Remove the top layer of parchment. If making a single large tart, use the bottom piece of paper to invert the dough into a tart pan. Remove the paper and press the dough evenly into place with your fingers. If making tartlets, cut dough into circles ½” larger than your tartlet pans and press circles evenly into pans. If there are any tears in the crust, simply pinch together or patch using a little of the excess dough. Cover loosely with plastic wrap and refrigerate for at least an hour.
- 3. Preheat your oven to 375 degrees. Bake the tart shell(s), without weights, for about 10-12 minutes until golden. Cool the shell on a wire rack. When ready to serve, fill the shell with 2 jars of your favorite American Spoon Preserves and bake an additional 3-5 minutes for tartlets or 10 minutes for a single tart.