The lightest and crispiest sourdough discard crackers with the best flavor.
Preheat oven to 325°.
In a large bowl combine the discard, olive oil, salt and half the rosemary. Whisk well to combine. The batter should be smooth without any visible oiliness.
Line a half sheet pan (18x13) with parchment paper. Spread the batter out to the edges of the pan in a smooth even layer.
Sprinkle the top of the batter with the remaining rosemary and some (2 grams) flaky salt if desired.
Place the sheet pan in the middle of the preheated oven and bake for 30 minutes.
After 30 minutes remove the pan and use a pizza cutter to score the batter into cracker sized squares. Or you can skip this step and break the crackers when fully cooked.
Return the pan to the oven and continue baking for 30 more minutes.
Remove the baked crackers from the oven and allow them to cool completely before breaking them along the scored lines. Store them in an air tight container.