Preheat the oven to 400ºF and set out either a 24-hole non-stick mini muffin tin or a large-rimmed baking sheet lined with parchment.
Measure 1 teaspoon of finely shredded parmesan cheese per hole in a mini muffin tin, or mound 1 teaspoon of cheese (evenly spaced) on a lined baking sheet.
Once the oven has preheated, add the mini muffin tin or baking sheet to the oven.
Cook for 4-6 minutes, or until the cheese is bubbly, melted, and brown. In tests, 5 minutes was the sweet spot.
Remove the baking sheet from the oven and allow the parmesan crisps to cool in the pan for 5-10 minutes, or until they are no longer pliable.
Line a plate or tray with 2-3 layers of paper towel, and gently transfer the parmesan crisps to the lined plate to drain.
Once the parmesan crisps are completely cooled and drained they are ready to serve and enjoy.
Notes
Storage: To store your crisps, allow them to cool to room temperature completely before transferring them to a plastic storage bag or airtight container. They will maintain their crispness for up to 12 hours, but you can re-crisp them in the oven at 400ºF for 2-3 minutes or in the air fryer at 375ºF for 1-2 minutes. Leftover crisps will store on the counter for 1-2 days, or in the fridge for up to 1 week, although they become quite chewy once stored in the fridge.Other cheeses: Feel free to experiment by substituting the parmesan cheese for your favorite aged cheeses. Just be sure to shred them using the small holes on your box grater.