In a medium bowl, melt butter nearly all the way. Allow to cool just a bit before stirring in the sourdough discard. I like to use a fork to incorporate. Sprinkle in ½ teaspoon salt and nutritional yeast. Stir well.

Add the flour and stir with the fork until well combined. Knead just a couple turns. Then wrap the dough in plastic wrap and chill for an hour.

Meanwhile, preheat the oven to 375 F. Once the dough has finished chilling, place on a large piece of parchment paper. Sprinkle with just a bit of flour on the rolling pin and roll as thin as you can (about 1-2 mm). Sprinkle with remaining ½ teaspoon salt.

Place on a baking sheet and bake for 5-8 minutes. Remove and score the crackers with a pizza roller. Place back in the oven for an additional 10 minutes. Inevitably, the edges will bake quicker than the inside. I like to pull the crispy outside ones and then back it another 4-8 minutes, checking to pull other crispy ones and returning to bake a bit more. Allow crackers to cool and then store in an airtight container.