Stir-Fried Carrots and Fennel with Garlic

The combination of carrots and fennel appeals to me, both flavorwise and visually. Root vegetables are typically thought of as candidates for braising, but when they are cut into thin sticks, they are perfect for stir-frying, and that makes for a quick side dish. I always feel a bit cheated when I see fennel bulbs sold with their stalks trimmed off, because I like the look and taste of the feathery fronds. If the only bulbs you can find are trimmed, substitute flat-leaf parsley for the garn