2 large fennel bulbs, trimmed and quartered
Olive oil spray (may substitute 1 tablespoon olive oil)
2 tablespoons grated Parmegiano Reggiano cheese
½ teaspoon kosher salt
½ teaspoon dried thyme
Preheat oven to 250 degrees F and line 2- 3 large sheet pans with either parchment paper or aluminum foil.
Trim the fronds from the fennel bulbs and divide bulbs into quarters, without removing core. The core will keep the slices intact.
Using a sharp knife or a mandolin, slice the quartered fennel bulb into slices 1/16″ thick. Place sliced fennel in a single layer on sheet pans, spray with olive oil and sprinkle with Parmegiano Reggiano cheese, salt and dried thyme.
If choosing to use olive oil, place sliced fennel in a bowl, add 1 tablespoon of olive oil, Parmegiano Reggiano, salt, thyme and toss before placing on sheet pan.
Bake fennel for at least 60 minutes until they appear crispy and the ends start to curl up. If not crispy, continue baking, checking fennel at 10 minute intervals.
Remove from trays and cool. Fennel will crisp a little more as they cool.