Preheat oven to 350 degrees. Use convection or air fryer setting if you have one. Line a baking sheet with parchment paper. Lay breaded fennel out in a single layer. Spray with olive oil, flip and spray the other side lightly. Bake about 20 minutes, flipping at mid point. Check them for crisp exterior and soft interior after about 15 minutes. Time will vary depending on your oven settings.