Trim the bottom end off of Brussel sprouts and slice them in half. For extra large ones, quarter them.
Rinse and soak them in cold water for 10 minutes. This will help the sprouts taste more tender in the center. Make sure you drain and pat them dry with a clean kitchen towel.
Preheat your air fryer at 400F for 5 minutes. In the meantime, toss the sprouts with olive oil, salt, garlic powder, and maple syrup in a large mixing bowl.
Add the sprouts to the fryer basket and spread them out to an even layer. Some overlap is okay. Air fryer for 10 minutes. Toss the basket after 5 minutes to ensure evenly cooking on all sides.
In a separate small bowl, make the maple lemon sauce.
Transfer the brussels sprouts to a serving bowl and toss with the maple lemon sauce. Taste and adjust with more salt, if needed. Serve warm.
Notes
To make this in the oven: Toss sprouts as directed, and spread them on a baking sheet in a single layer. Bake at 400°F for 35-40 minutes, shaking pan occasionally, until browned and tender.
The secret to crispy outside and tender inside brussels sprouts is to soak them. Soaking the Brussel sprouts for 10 minutes prior to cooking prevents the sprouts from burning, drying, and perfectly cooking sprouts.