Preheat the oven to 425°F. Line a rimmed baking sheet with parchment paper.
In a large bowl, combine the potatoes, carrots, onion, olive oil and garlic; toss well to coat. Arrange the vegetables in a single layer on the prepared pan. Sprinkle with salt and pepper. Bake for 30 minutes, turning after 15 minutes or until tender and lightly browned.
In a large bowl, combine the vegetables, chives, zest and juice; toss gently to coat. Serve immediately.