Preheat your oven to 300°F and line two baking sheets with parchment paper. While the oven heats, wash the kale thoroughly under cold water and pat it completely dry with paper towels or a clean kitchen towel—this is crucial for crispiness, as any moisture will create steam and make the chips soggy rather than crispy. Remove the tough center stems and tear the leaves into roughly 2-inch pieces, aiming for uniform size so everything crisps evenly.

In a large bowl, combine the torn kale with the olive oil, apple cider vinegar, and salt. Using your hands or two spoons, toss everything together for 1 to 2 minutes, making sure every piece of kale gets evenly coated with the oil and vinegar mixture. I like to massage the kale a bit with my hands—this helps the seasonings really stick and begins to break down the leaves slightly, which improves texture. Don't skip this step; thorough coating is what gives these chips their signature tangy, salty flavor.

Spread the seasoned kale in a single layer across your prepared baking sheets, making sure pieces don't overlap too much—crowding them will trap steam and prevent crisping. Bake for 18 to 22 minutes, checking around the 15-minute mark. The chips are done when the leaves are completely dry and crispy to the touch; they should shatter easily when you break one. Remove from the oven and let cool for 1 to 2 minutes on the pan, then sprinkle with the nutritional yeast for an extra layer of umami and a subtle cheesy note.

Transfer the kale chips to a serving plate or bowl and enjoy immediately while they're at their crispiest. If you have leftovers, store them in an airtight container at room temperature for up to 3 days—I've found that keeping them in a container with a small silica packet helps them stay crispy longer.