In a microwavable bowl, weigh out 50g of butter, then place into microwave to melt. Add the bowl back on the scale and zero out.
Pour 200g of sourdough discard into the bowl. Mix butter and sourdough discard until well combined.
Prepare a large baking sheet and cover with parchment paper.
Pour mixture onto parchment paper and using the spoon spread it out until it's as thin as possible.
Add desired toppings.
Place in preheated oven for approximately 20 minutes. More or less depending on your oven. You want the cracker to be brown on the edges and slightly golden in the middle for optimal cracker.