1/3 c. red wine vinegar
1/3 c. salad oil
1 sm. onion, thinly sliced and separated into rings
1 tsp. salt
2 tsp. dried parsley flakes
1 tsp. prepared mustard
1 tbsp. brown sugar

Combine ingredients in a small saucepan and bring to a boil. Add 2 (6 ounce) cans mushroom crowns, drained; simmer 5-6 minutes. Chill in a covered bowl several hours, stirring occasionally. Drain. Makes 2 cups.