Tomatoes Vinaigrette

8 to 12 thick tomato slices
1 cup olive oil or salad oil
1/3 cup wine vinegar
2 tsp. oregano leaves
1 tsp. salt
1/2 tsp. pepper
1/2 tsp. dry mustard
2 cloves garlic, crushed
crisp lettuce
minced green onion
snipped parsley
3 to 4 servings
Arrange tomatoes in baking dish.
In tightly covered jar, shake oil, vinegar, oregano, salt, pepper, mustard and garlic; pour over tomatoes.
Cover and chill 2 to 3 hours, spooning dressing over tomatoes occasionally.
Just before serving, arrange tomatoes on lettuce.
Sprinkle tomatoes with onion and parsley; drizzle some of the dressing over top.