Preheat oven to 425F and line a baking sheet with aluminum foil or parchment.
Take the stalks off the fresh fennel bulb and roughly chunk the bulb.
Toss the fennel with olive oil, salt, and pepper and lay out spaciously on the sheet pan. Don't overcrowd the pan.
Roast for ~12 minutes. Remove from oven, move fennel around, and place back in oven for ~10-12 minutes or until browned and caramelized.
Notes
Wanna up your game? Cool - chop some of the fresh fennel leaves and use them as a garnish.
Some of the more tender "fingers" / stalks originating from the bulb can be chopped and roasted as well. See / hear the video for more explanation. The stalks closest to the bulb will be tender but the further out you go the skin will become tough and fibrous.
Fennel not browning? Up your temperature to 450F and / or up your time. All ovens are different.
Lastly, don't overcrowd the sheet pan or it will steam and not roast/brown properly. See image above for spacing on the pan.