01 - Preheat the oven to 350°F. Line a baking sheet with parchment paper.
02 - In a mixing bowl, combine sourdough discard, cheddar, softened butter, salt, garlic powder, and paprika. Mix until well incorporated.
03 - Gradually add flour, mixing until a shaggy dough forms. Add just enough cold water, 1 tablespoon at a time, to bring the dough together.
04 - Turn the dough onto a floured surface and knead gently until smooth.
05 - Roll out the dough to about 1/8-inch thickness. Use a sharp knife or pizza cutter to cut into 1-inch squares.
06 - Transfer the squares to the prepared baking sheet. Prick each cracker with a fork and sprinkle with coarse sea salt.
07 - Bake for 16–20 minutes, or until golden and crisp. Rotate the tray halfway through for even baking.
08 - Let the crackers cool on a wire rack. Store in an airtight container at room temperature for up to 1 week.