Preheat oven to 425 degrees. Trim the outer leaves from Brussels sprouts. Cut large ones in halves or quarters and add to a large mixing bowl. Add onion, pecans and olive oil then toss to coat. Pour onto a rimmed baking dish and sprinkle evenly with salt.
Roast for 13–14 minutes, then toss and continue cooking another 5–10 minutes or until the Brussels sprouts reach the desired level of doneness. Remove from oven and transfer to a serving bowl. Sprinkle feta cheese and pepper over the top and toss to combine. Serve immediately.
Notes
If you’re using frozen Brussels sprouts, make sure they are fully thawed and drained to get rid of their excess moisture before roasting!