Line a large sheet pan with parchment paper and set aside.
Wash the Brussels sprouts and pat dry. Remove any yellow outer leaves, and trim off the brown end of the stem. Then cut each one in half and place in a large bowl.
Add the oil, salt and pepper to the bowl. Toss to coat the sprouts.
Arrange the sprouts, cut side down, on the parchment-lined pan. Pour any remaining oil in the bowl over the sprouts.
Roast the sprouts in the oven until they are brown and tender. This should take 25-30 minutes, depending on how big your sprouts are.
Meanwhile, add the butter to a small saucepan and place over medium heat. The butter will eventually begin to foam. Swirl the pan gently and look at the colour of the melted butter. When it turns golden brown, and smells nutty, it's done. Set it aside.
When the sprouts are finished roasting, pour the brown butter over them and top with toasted nuts. Serve warm.
- I used grapeseed oil in this recipe because it has a higher smoke point than olive oil, and a neutral flavour. If you don't have grapeseed oil, you can use vegetable oil, canola oil or even light olive oil. I've used all of these before and they turn out just fine - the flavour is just slightly different.
- Brown butter is usually made with unsalted butter, but I always make mine with salted butter because that's usually what I have in the house and it works!