Preheat the oven to 350 degrees F.
Line 2 baking sheets with parchment paper.
In a food processor, combine the cheese, flour, paprika, onion powder, garlic powder, and salt.
Pulse until the cheese mixes into the flour.
Add the butter and starter if using and pulse until the mix clumps together to form pea-size balls. Add the water, 1 tablespoon at a time, until the dough comes together and forms a ball.
Turn the dough out onto a floured surface and form into a ball. Divide the dough in half. Working with one section of dough at a time. Roll the dough as thin as you can, about a 1/8-inch thick. Cut into 1/2-inch to 1 inch squares. Repeat with the remaining dough.
Carefully transfer the cut outs to the prepared baking sheet, spacing them a 1/2 inch apart. Poke a hole in the middle of each square. Sprinkle with flaky sea salt, if desired.
Bake 15-16 minutes, until golden. Let cool completely, then store in an airtight container for up to 1 week.
