In a bowl, mix sourdough discard, egg, olive oil, and salt until combined.

Gradually add flour and mix until a shaggy dough forms.

Knead on a floured surface for 6 to 8 minutes until smooth and elastic.

Cover and let the dough rest for 20 to 30 minutes.

Divide dough and roll into thin sheets about 1 to 2 mm thick.

Dust with flour or cornstarch, roll loosely, and slice into noodle strips.

Unroll noodles and toss lightly with flour to prevent sticking.

Bring salted water to a boil and cook noodles for 2 to 4 minutes.

Drain and serve immediately with desired sauce or broth.