Updated: Aug 26, 2021
Last spring, we had a couple friends over for outdoor pizza-making. Our neighbor gave us a few peanut butter cookies for dessert, the classic ones with the crisscross fork print on the top. One of our friends picked up the bottle of balsamic reduction that we'd been using as a pizza topping and squirted a little on the cookie. It was delicious. The tangy sweetness of the balsamic reduction somehow worked with the peanut butter cookie. Balsamic does come from grapes after all, and what better American guilty pleasure food combo is there than the peanut butter and jelly sandwich? With that in mind, I decided I would attempt a more adult version of the cookie with balsamic glaze (recipe link). It took a few attempts and a number of weird balsamic-y icing failures but I finally produced something I am proud of!
At first, I thought I would do a slice and bake cookie. I used confectioners sugar in the dough to result in a more crumbly cookie once baked. I combined balsamic with confectioners sugar to make a (gross-looking) dark brown icing in an attempt to stay close
to the original balsamic topping. I did not take a photo of that. The cookies were good and pretty, but we ended up enjoying them more at breakfast time than as a dessert. For this reason, changing from a cookie to a bar seemed to make sense. Sure, we're still eating cookies for breakfast but it feels better in bar shape.
The first pass at a bar was not too far off from where I wanted to be. I changed my thinking about the icing to be more in line with classic cake icing; smooth, creamy, appetizing. I added creamy peanut butter to it, reduced grape juice to form a thick grape concentrate and combined them with balsamic vinegar and confectioners sugar. I liked the result, but
because I was going for an icing, this meant a lot of confectioners sugar which meant I had to use a little food coloring to get the purple color I was after. And I still didn't get the color. I don't like using food coloring, so I was already re-thinking this icing approach. I asked some girlfriends to taste them and provide feedback, which they did and which was very helpful in moving this little experiment along.
The bars needed a little more substance and a little more sugar. The latter was easy enough, and for the former I decided to incorporate lightly sweetened oats. If we are eating these at breakfast as well as dessert, oats would be a welcome addition. I soaked them in a mixture of warm water, maple syrup, and a pinch of salt while I continued making the batter. It worked well to moisten the oats since the batter is rather thick. For the icing, I went back to basics - balsamic, grape juice, and confectioners sugar. To get a darker color without food coloring I decided a glaze, which is thinner than an icing, would be just perfect. And it was. Top with toasted crushed peanuts, and you've got yourself a breakfast or dessert bar!
One 9x13 pan of Bars, cut as desired
Stand or hand mixer
FOR THE BARS
1 tablespoon maple syrup or brown sugar
2 tablespoons warm water
pinch of salt
1 cup whole grain oats (80g)
3/4 cup unsalted butter, at room temperature (175g)
1/2 cup confectioners sugar (50g)
1/2 cup packed brown sugar (100g)
2 large eggs, at room temperature
1 cup chunky or smooth peanut butter (256g) - your preference, or whatever you have in the pantry!
1/2 teaspoon almond extract
1 teaspoon salt
2 cups all-purpose flour (250g)
handful of dry roasted and shelled peanuts
FOR THE ICING
2 tablespoons grape juice
1 tablespoon balsamic vinegar
2 cups confectioners sugar (200g)
1---Preheat oven to 350F and line a 9x13 baking dish with parchment. In a small bowl, combine the maple syrup (or brown sugar) with warm water and salt and mix until dissolved. Then add the oats and stir to moisten. Let these sit and fully absorb the liquid while continuing.
2---In the bowl of a large stand mixer, cream the butter and sugars on medium-high until smooth and fluffy, about 2 minutes, scraping down the sides of the bowl as necessary. Turn the speed to medium-low and add the eggs, peanut butter, almond extract, and salt. Once combined, add the flour a little at a time and mix until combined. The batter will be thick. At this point, as with anything I use a mixer for, I like to turn it on super-high speed and slowly lift the paddles out of the bowl, allowing the batter to fly off and onto the sides of the bowl. This reduces the amount of paddle scraping you'll have to do.
3---Empty the mixing bowl contents into the prepared 9x13 pan and using a spatula, push it around until it is roughly distributed. Next, take another piece of parchment and lay it on top. Working with your hands, push the batter into place until it is evenly distributed. Use your fingertips to dimple the parchment, or use a ravioli wheel to make a crisscross pattern across the top. This will give our bars some surface texture, like the original peanut butter cookies have.
4---Bake for 25 minutes. While baking, make your icing and prepare the peanuts for topping. Combine the icing ingredients and spoon into a piping bag with a small hole attachment, or into a plastic ziplock bag. If using a plastic bag, you'll snip off the end right before icing to make a small hole. (Tip: Do not use a "stand-and-fill" bag because they don't work for this.) Crush the peanuts, place on foil, and toast for a minute or two until just beginning to brown.
5---Remove the peanut butter sheet from the oven and allow it to cool on a wire rack for 10 minutes. Lift it out of the pan with the parchment and return to the wire rack to cool completely. Once cool, I like to trim the ends to make it neat and set these aside to snack on. Drizzle with icing and top with crushed peanuts. Cut as desired. Enjoy!