01 -
Heat your oven to 350°F and put parchment on a cookie sheet.
02 -
Mix your cooled butter with the sourdough discard and salt, then add the grated cheese and mix until everything's combined.
03 -
Use an offset spatula to make the mixture super thin on the parchment until you can almost see through it (roughly 11x14 inches).
04 -
Sprinkle a bit of chunky salt or whatever topping you fancy.
05 -
Pop in the oven for 10 minutes, take it out and cut into squares with a pizza cutter. You can poke middle holes with a skewer if you want.
06 -
Stick it back in the oven for about 20 minutes until it's golden and sounds firm when you tap it.
07 -
Let them cool completely on the tray before you put them in a sealed container.