Combine tomatoes and boiling water in a bowl; cover and let stand 15 minutes or until softened. Drain well, and finely chop. Place flour in a small saucepan, and gradually add milk, stirring with a whisk until blended. Stir in tomatoes, pan drippings, green onions, salt, basil, and pepper. Cook over medium heat 5 minutes or until mixture is thickened, stirring constantly with a whisk.