In a heavy saucepan, heat the oil and add onion, garlic, and carrots. Cook, stirring often, for 4 minutes or until onion has softened. Stir in barley, and then pour in stock.
Put mixture into a casserole dish, cover and bake in a 350ºF (180ºC) oven for 1 hour. Stir in corn, parsley, salt and pepper to taste.
Bake for another ten minutes or until heated through and barley is tender. Serve hot.
Can also be covered and refrigerated for up to 2 days. To reheat, stir in 1/2 cup stock or water.