Barley and Sweet Potato Pilaf

Place the onion in a large saucepan and sauté over medium heat for 6 minutes.

Add water 1 to 2 tablespoons at a time to keep the onions from sticking to the pan.

Add the garlic and cook 3 minutes more.

Add the vegetable stock and barley and bring the pot to a boil over high heat.

Reduce the heat to medium and cook, covered, for 30 minutes.

Add the sweet potato and cook for 15 minutes longer, or until the potatoes and barley are tender.

Stir in the tarragon and lemon zest and juice, and season with salt and pepper.