Step 1: Preheat your oven to 375°F (190°C). Line two baking sheets with parchment paper.
Step 2: In a medium bowl, combine the sourdough discard, all-purpose flour, 2 tbsp granulated sugar, 1 tsp ground cinnamon, and a pinch of salt. Mix until a shaggy dough forms.
Step 3: Turn the dough out onto a lightly floured surface and knead briefly (about 1 minute) until it comes together into a smooth ball.
Step 4: Divide the dough in half. On a lightly floured surface, roll one half of the dough out very thinly, about 1/16-inch thick. The thinner you roll it, the crispier your crisps will be!
Step 5: Brush the rolled dough lightly with half of the melted butter.
Step 6: In a small bowl, mix together the 2 tbsp granulated sugar and 1 tsp ground cinnamon for the topping. Sprinkle half of this mixture evenly over the buttered dough.
Step 7: Using a pizza cutter or sharp knife, cut the dough into desired shapes (squares, triangles, or strips). Transfer the crisps to the prepared baking sheets, leaving a little space between each.
Step 8: Repeat Steps 4-7 with the remaining dough, butter, and cinnamon sugar mixture.
Step 9: Bake for 15-20 minutes, or until golden brown and crispy. Keep a close eye on them as they can brown quickly.
Step 10: Remove from the oven and let cool completely on the baking sheets. They will crisp up further as they cool.