Preheat oven to 400° and line a baking sheet with tin foil.
Slice each Brussels sprout in half lengthwise, toss them in olive oil and place them in a single layer on the baking sheet.
Mix together breadcrumbs, parmesan, salt, pepper, and lemon zest in a small bowl.
Cook the brussel spouts for about 30 minutes, pull them out of the oven and coat with the breadcrumb mixture and then place them back in the oven to cook for 5-10 minutes until the cheese has melted.
Servings 4