Heat the oven to 400°F / 200°C convection roast or 425°F / 220°C conventional with the rack in the middle.
While the oven is heating up, whisk together the All-Purpose Stir-Fry Sauce, avocado oil, arrowroot powder, and kosher salt in a liquid measuring cup or bowl.
In a large bowl, combine the chicken, sugar snap peas, shiitake mushrooms, carrots, shallot, and garlic. Pour in the sauce and toss well to combine.
Grease a rimmed baking sheet with avocado oil or line it with parchment paper. Transfer the chicken and veggies to the baking sheet and arrange in a single layer.
Bake for 14 to 17 minutes, rotating the pan at the midway point. The sheet pan chicken dinner is ready when the vegetables are tender-crisp and browned in parts and the chicken is cooked through.
Sprinkle on the sliced scallions and serve with some simple cauliflower rice!