Place potatoes in medium saucepan; cover with cold water. Bring to a boil. Reduce heat; cook 15 to 20 minutes or until tender. Drain.
Cut potatoes in half. If necessary, cut thin slice from bottom of potato halves to level. With small spoon or melon baller, scoop out center of cooked potatoes, leaving 1/8-inch shell. Place scooped out potato (not shells) in small bowl. Add 1 teaspoon chives, thyme, salt, garlic powder, sour cream, margarine and milk; mash until smooth.
Pipe or spoon potato mixture into potato shells. Place on ungreased cookie sheet.
Broil 4 to 6 inches from heat for 3 to 5 minutes or until hot and lightly browned. Sprinkle with paprika and chives. Arrange filled potatoes on serving plate. If desired, garnish plate with fresh thyme.