In a large skillet, heat the butter/margarine and oil over medium heat. Lightly brown the chicken breast halves. Add the garlic, leek and onion and saute until they begin to soften. Add the potatoes and carrots, then add chicken broth, water, bay leaf, pepper and parsley. Simmer all together for 30 minutes or until vegetables are soft.

Combine 2 tablespoons each flour and water and mix together (done easily if you shake together in a jar). Turn up heat under skillet and add flour/water mixture to thicken the juices.