Preheat and prep pans: Heat the oven to 425°F (220°C). Line 2 large baking sheets with parchment paper and set an oven rack in the upper third and another in the lower third. This helps air circulate and encourages crisping.

Slice the zucchini: Wash and dry the zucchinis thoroughly. Using a mandoline if possible, slice into thin rounds about 1/8 inch (3 mm) thick. Consistent thickness is key to even baking.

Salt and drain: Place slices in a colander and toss with 1/4 teaspoon kosher salt. Let sit for 10–15 minutes to draw out moisture. After resting, gently pat the slices very dry between layers of paper towels or a clean kitchen towel.

Make the coating: In a shallow bowl, mix Parmesan, panko, garlic powder, onion powder, smoked paprika (if using), a pinch of black pepper, and a small pinch of salt. Taste the mixture—Parmesan is salty, so season lightly.

Oil the slices: Transfer zucchini to a large bowl and drizzle with olive oil. Toss to coat lightly and evenly. You want a thin sheen, not heavy oil.

Coat and arrange: Press each slice into the crumb mixture to lightly coat one side. Arrange, crumb-side up, on the prepared baking sheets in a single layer with a little space between slices. Do not overlap.

Optional mist: For extra crunch, lightly mist the tops with cooking spray. This helps the coating brown more evenly.

Bake and rotate: Bake for 12 minutes, then swap the sheet positions (top to bottom, front to back). Continue baking for another 8–12 minutes, watching closely in the final minutes. They’re done when edges are deep golden and centers are crisp-tender.

Final crisp: If some chips are browning faster, remove them and return the rest to the oven for 2–4 minutes more. Avoid overbaking; they can turn bitter if too dark.

Cool and season: Let the chips cool on the pan for 5 minutes to set their texture. Taste and sprinkle with a pinch more salt if needed. Serve warm with lemon and your favorite dip.