In a mixing bowl, thoroughly combine the sourdough starter, cornmeal or masa, salt, and oil/butter.
Divide the large dough ball into two equal sized balls.
Next shape and squish each dough ball into a patty like rectangular shape until the dough thickness is about a half inch.
Place the rectangular dough patties on their own plates and cover with plastic wrap, parchment paper, or beeswax wrap. Place in the refrigerator for at least 30 minutes or up to several hours hours.
Preheat the oven to 350 degrees Fahrenheit.
Place the patties of dough each on their own piece cornmeal-dusted parchment paper, dust the top of the dough with cornmeal, and roll out with a rolling pin until dough is nice and thin, about 1/16th of an inch thick. The thinner they are, the more crisp they'll be!
Lightly brush the dough with extra virgin olive oil, and lightly sprinkle salt over the top.
Cut the dough using a pizza wheel into 1 to 2 inch squares, strips or triangles.
Transfer the parchment paper of raw chips on to a baking sheet and place in the oven for approximately 25 minutes* (see recipe notes below) until the chips are lightly golden brown and crisp.
Rotate the baking sheets halfway through to help the chips bake evenly.
Once finished baking, quickly remove the chips to a cooling rack.
Once cool, enjoy the chips immediately or store them in an airtight container to enjoy later.