Preheat oven to 400 ℉. Line a metal sheet pan with parchment paper or silicone baking sheet.
Toss all ingredients together, except vegan parmesan cheese, in a large mixing bowl. Transfer the marinated brussels sprouts and onion onto the baking sheet. Spread to form a single layer without any overlapping. Try to place the cut side of brussel sprouts facing up to give them a little bit of char once baked.
Bake 35 minutes until the brussels sprouts are golden brown. Sprinkle some vegan parmesan cheese if prefered. Serve hot.
Sheet Pan Rosemary Garlic Brussels Sprouts https://lightorangebean.com/sheet-pan-rosemary-garlic-brussels-sprouts/