Preheat the oven to 450°F. Line a rimmed baking sheet with aluminum foil.
In a large bowl, combine the Brussels sprouts, pears, and onion and toss to coat with the olive oil. Season with a few pinches each of salt and pepper.
Transfer to the prepared baking sheet and bake until the Brussels sprouts are golden brown and have started to crisp and the pears have caramelized, 25 to 30 minutes, stirring once halfway through cooking.
Squeeze the lemon wedges over the pan and drizzle with the honey. Toss in the dried cranberries, mix everything well, and taste, adding another squeeze of lemon or more salt and pepper if desired. I promise this dish will not disappoint.