Preheat oven to 425 degrees F and prepare a baking sheet.
Bring brussels sprouts to a boil in a large pot, let cook until very tender, then drain.
Transfer to the baking sheet and toss with olive oil. Using a drinking glass, press down on each brussels sprouts to smash. Top with vegan cheese, salt, and pepper.
Bake for 20-30 minutes, until the bottom of the brussels sprouts are crispy and the cheese is fully melted.