Serves 12-16
2 sticks unsalted butter, softened
1 1/2 cups packed light brown sugar
2 egg yolks
1 teaspoon vanilla
2 1/4 cups all purpose flour
1/2 teaspoon baking soda
1/2 teaspoon fine salt
1/2 cup chocolate discs
1/3 cup mini semisweet chocolate chips
1/2 cup cookie butter
Flaky sea salt
Preheat oven to 325 degrees. Lightly grease an 8x8” baking dish with the end of one stick of butter. Cut the butter into cubes and add to a standing mixer. Add brown sugar and mix until combined and fluffy. Add egg yolks and vanilla, continuing to mix. Add baking soda and salt, followed by 1/2-cup portions of flour, waiting for dough to incorporate before adding more. Note: you might not need the final 1/4 cup of flour! Judge your consistency after 2 cups to check dough has reached its familiar cookie dough form. Remove bowl from stand mixer and fold almost all of the chocolate discs and chips into dough — save a small handful to dot the top of the dish.
Transfer half of the dough to baking dish and, using your hands, press dough into an even layer. Spread cookie butter evenly atop cookie dough. Add remaining dough in dollops on top of cookie butter and carefully press to evenly distribute. Press in remaining chocolate and transfer to oven. Bake 30-35 minutes, rotating pan 180 degrees halfway though. The edges should be golden and crispy, and the center should appear slightly underbaked. Remove dish from oven and immediately sprinkle with flaky sea salt. Allow to completely cool before slicing into desired squares or rectangles.
Store in refrigerator. Microwave a bar for 8 seconds, if desired! Freezes well.
