The vegetable measurements are simply a guide. You can add more, or use different vegetables depending on your taste and what’s in season. If you’re looking for ideas, you might consider leeks, broccoli, cauliflower, etc. If you’ve like to serve potatoes or a starchy vegetable along with your roasted chicken then cut them into wedges, toss with butter, salt and pepper and place in a baking dish and bake along-side the chicken.
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