Heat oven to 350°F. Melt margarine in small skillet over medium heat. Add onions and garlic; cook and stir 5 to 8 minutes or until onions are tender. Remove from heat; cool slightly. Stir in parsley.
Separate dough into 8 biscuits. Spoon onion mixture on 1 side of each biscuit. Stand biscuits on rounded edge in ungreased 8x4 or 9x5-inch loaf pan, with plain side of end biscuits towards pan.
Bake at 350°F. until deep golden brown. Bake 8x4-inch pan 50 to 60 minutes; bake 9x5-inch pan 35 to 45 minutes. Cover with foil during last 10 to 15 minutes of baking to prevent excessive browning. Immediately remove from pan. Serve warm.