Step 1: Preheat your oven to 400°F (200°C) and line a large rimmed baking sheet with parchment paper for easy cleanup.
Step 2: In a large mixing bowl, toss the trimmed and halved Brussels sprouts with olive oil, salt, and pepper until evenly coated.
Step 3: Spread the sprouts in a single layer on the prepared baking sheet, ensuring they have enough space to roast properly.
Step 4: Roast for 15-20 minutes, then remove the tray and add the walnuts and dried cranberries, tossing them with the sprouts.
Step 5: Return to the oven for an additional 5-7 minutes until the sprouts are tender and charred and the walnuts are fragrant.
Step 6: Remove from the oven, drizzle with maple syrup or balsamic glaze if desired, and serve your roasted brussels sprouts with cranberries and walnuts warm.