Herbed Yogurt Baked Tomatoes

1/2 cup plain nonfat yogurt
1 1/2 teaspoons all-purpose flour
1/2 teaspoon dried marjoram
1/4 teaspoon salt (optional)
1/4 teaspoon ground black pepper
2 large unpeeled red tomatoes (about 1 pound)
Vegetable cooking spray
1/4 cup grated fresh Romano cheese

Combine yogurt, flour, marjoram, salt and pepper; stir well and set aside.

Core tomatoes and cut each in half horizontally. Push seeds out of middle section of tomatoes with thumbs. Place tomato halves, cut sides up, in an 8-inch square baking dish coated with nonstick cooking spray. Spoon 2 tablespoons of the yogurt mixture over each tomato half. Sprinkle 1 tablespoon of the Romano cheese on top of each one. Bake at 400 degrees F for 30 minutes, or until lightly browned.

Makes 4 stuffed tomato halves.