1/2 c. catsup
1 med. onion, chopped
3 tbsp. brown sugar
2 tbsp. vinegar
1 tsp. basil
1/2 tsp. garlic salt
1/4 tsp. thyme
1/2 tsp. salt
1/8 tsp. pepper
3 lb. brisket

Combine all sauce ingredients in a small bowl. Place brisket in an oblong casserole and cover with half of sauce. Seal with plastic wrap, turning back one corner to vent. Microwave on HIGH for 15 minutes; lower to MEDIUM for 45 minutes. Turn brisket over and add other half of sauce. Microwave at MEDIUM 45 to 60 minutes, until tender. Let stand 10 minutes. Carve in thin slices and serve with sauce. Serves 6 to 8.