I made these during Covid-19 lock down. I usually translate all the measurements in recipes from Great Britain into American but I found the recipe to be enjoyable as it is so I am just saving it pretty much like he wrote it.
The Boy Who Bakes
225 g unsalted butter, diced
380 g plain flour
1 teaspoon baking powder
1 teaspoon baking soda
1 teaspoon flaked sea salt
220 g caster sugar
220 g light brown sugar
3 large egg yolks
240 g sourdough starter discard (100% hydration)
1 teaspoon vanilla extract
500 g dark chocolate, roughly chopped
To make the cookies we first need to brown the butter. Don’t be tempted to skip this because this isn’t just done for flavour it also removes the water content from the butter which is being replaced by the starter, if you skip this step the resulting recipe will have a very different texture. Place the butter into a saucepan and over medium/high heat cook until the butter melts, bubbles and then foams. Keep a close eye on it as it can burn quickly, when the milk solids have browned the water will have been evaporated off so remove from the heat and set aside for 30 minutes or so, to cool slightly. Once browned you should have 185g unsalted butter left (that’s if using butter with an 82% fat content).
Whilst the butter is browning, place the flour, baking powder, baking soda and salt into a large bowl and whisk together to combine. When ready to make the cookies place the butter and sugars into a large bowl and using an electric mixer, fitted with the whisk attachment, whisk for a couple minutes to combine and to break up any lumps.
Add the egg yolks and whisk for 2-3 minutes on medium/high. Don’t worry if this looks separated or greasy at the moment, it will come together once we’ve added the starter.
Place the bowl on your scale and measure in the required sourdough discard, adding the vanilla as well.
Mix in for a few minutes or until the mixture becomes smooth and fully combined, it should look a little like a thick cake batter.
Add in the flour mixture and mix in on low speed, just until everything comes together as a dough.
Finally, switch to the paddle attachment and add the chocolate, mixing briefly until evenly distributed. Press a sheet of clingfilm onto the surface of the cookie dough and refrigerate for at least 4 hours before baking (my preferred time frame to bake these is between 4-24 hours). When ready to bake preheat the oven to 180C (160C Fan) and line a couple baking trays with parchment paper. Roll the cookies into balls roughly 70g in size, placing 6 per baking tray, with plenty of space between each one as these will spread. Sprinkle the cookies with a little flaked sea salt.
Bake in the preheated oven for about 16-18 minutes or until the cookies are lightly browned around the outside. If the cookies come out a little puffy looking give the baking tray and firm tap on the counter to help them flatten a little. Allow to cool on the baking tray for 10 minutes before transferring to a wire rack to cool completely. Stored in a sealed container these will keep for 4-5 days. You can also freeze these balls of cookie dough for up to a month, baking straight from frozen with just a minute or two of extra bake time.
Note: With my regular cookie recipes I will leave the dough in the fridge for up to three days but with these remember that even though the discard may be less active than your usual starter you are adding sourdough to fresh flour so overtime the dough will ferment a little more, so the longer you leave the dough the stronger the finished flavour.
Once the dough is chilled and you’ve rolled them into balls you can freeze these for up to a month. To freeze place the balls onto a parchment lined baking tray that will fit in the freezer. Freeze the cookies until frozen solid, at this point the cookies won’t stick together so you can add them to a freezer bag or Tupperware to save on space.
For the chocolate I normally like a high-quality dark chocolate but you can really use whatever you have, be that a milk or dark, bars, chips or wafers. Each one will make a slightly different cookie with different textures and tastes but they’ll all be great.