Summertime Picnic Relish
["1 c. chopped onion", "1 c. chopped green pepper", "2 Tbsp. salad oil", "4 firm medium tomatoes, peeled and chopped", "2 Tbsp. vinegar", "1 1/2 tsp. salt", "1/2 tsp. sugar", "1/4 tsp. dry mustard", "1/8 tsp. pepper"]
["In large skillet, cook and stir onion and green pepper in oil over medium heat until onion is tender.", "Stir in remaining ingredients.", "Heat to boiling.", "Cool.", "Cover; refrigerate several days.", "Makes about 3 cups."]
["onion", "green pepper", "salad oil", "tomatoes", "vinegar", "salt", "sugar", "dry mustard", "pepper"]