Preheat oven to 400°F (use convection setting if your oven has it)
Rinse and dry Brussels sprouts stalk and place on a large rimmed baking sheet lined with parchment paper or a silicone baking mat.
Combine the avocado oil, maple syrup and balsamic vinegar in a small sauce pot over medium-low heat. Cook until heated through, whisking constantly, about 2-3 minutes.
Pour or spoon the mixture evenly over the Brussels sprouts stalk, turning the stalk as you pour to coat each side.
Season the stalk generously with Kosher salt and pepper.
Roast for about 30 minutes, turning the stalk on the baking sheet every 10 minutes.
Brussels sprouts should be a dark golden brown when finished and knife tender.
Remove from the oven, slice each Brussels sprout off the stalk with a sharp knife to serve.