Toss the Brussels sprouts with 1 tablespoon of olive oil in a large bowl. Transfer to a rimmed baking sheet and roast in the oven for about 20 minutes, or until tender and beginning to brown, stirring occasionally.
Transfer the gnocchi and Brussels sprouts to the large bowl. Toss with the lemon zest, pine nuts, and cheese, then season with salt and pepper to taste.
In Europe, Parmesan cheese is never vegetarian. Substitute a different kind of cheese if you're a strict vegetarian.