Heat oven to 350°F. In 4-quart saucepan, melt butter over medium-high heat. Add onions; cook 2 to 3 minutes, stirring frequently, until tender. Stir in flour, bouillon, thyme and pepper until well blended. Gradually stir in broth and milk, cooking and stirring until bubbly and slightly thickened.
Stir in potatoes, carrots and green beans. Heat to boiling, stirring occasionally. Cook 8 to 10 minutes, stirring frequently, until vegetables are crisp-tender.
Meanwhile, separate dough into 8 biscuits. Using rolling pin, roll each biscuit into a 4-inch round. Cut each round into 6 equal wedges; set aside.
Stir chicken into vegetable mixture; return to boiling. Remove from heat. Into each of 8 ungreased 10-oz custard cups or ramekins, spoon about 1 cup mixture. Place 6 biscuit wedges around edge of each, overlapping slightly and leaving hole in center for steam to escape.
Bake 20 to 25 minutes or until vegetables are tender and biscuits are golden brown. Let stand 5 minutes before serving.