Preheat your oven to 425°F. Line a rimmed baking sheet with heatproof parchment paper and spray the paper with olive oil.
In a shallow bowl, whisk the egg whites until frothy.
In another bowl, mix the almond flour, kosher salt, black pepper, garlic powder, paprika, and cayenne. Divide the mixture between two shallow bowls - this will help prevent the almond flour coating from becoming soggy.
Trim the zucchini ends and cut them into ¼-inch-thick fries. Pat them dry using paper towels.
Place the zucchini fries in the bowl with the beaten egg whites to coat. Dredge each zucchini strip in the seasoned almond flour, gently pressing to help it adhere. To prevent a sticky mess, it's best to use one hand to pick each zucchini strip up from the egg whites and the other hand to dredge it in the almond flour.
Place the coated zucchini strips on the prepared baking sheet, arranging them in a single layer. Lightly spray the zucchini strips with olive oil.
Bake the fries in the preheated oven for 15 minutes.
Remove the baking sheet from the oven. Carefully flip the fries (I use two spoons) and spray them again with oil.
Return the pan to the oven. Bake the fries until browned and crispy, for 10-15 more minutes.
Serve immediately, with a dipping sauce if desired.
Video
Notes
Some of the almond flour (about ¼ cup) will remain in the bowl, but you need all of it to dredge the fries properly. The nutrition info reflects that.
I don't use breadcrumbs in the coating, opting for almond flour. However, if you wish, you can substitute breadcrumbs (regular or gluten-free) for the almond flour, keeping in mind that the nutritional info will change.
As long as you pick firm zucchini, there's no need to salt it before baking. Salting helps draw water out, and it does have its place. But in this recipe, the high-heat baking takes care of that, so there's no need to pre-salt the zucchini.
Zucchini fries are best enjoyed fresh. But if you must, you can keep the leftovers in the fridge, in an airtight container, for up to 4 days. Place them on paper towels to absorb any extra moisture. Reheat them in a 350°F oven for about ten minutes or until heated through.