Ingredients

1 large white onion, halved crosswise, ends discarded, plus 1/2 onion coarsely chopped

5 tablespoons white vinegar

4 baby carrots

1 stalk celery, coarsely chopped

2 pounds ground beef

1 cup rolled oats or breadcrumbs

1 cup white rice

1 cup tomato sauce with garlic

1 cup cold water

1 heaping tablespoon red paprika

1 tablespoon vegetable herb seasoning, such as Vegeta

1/2 tablespoon chicken base

1/2 tablespoon fresh garlic in oil

1/2 tablespoon freshly ground black pepper

Directions

Step 1: Preheat the oven to 450 degrees F. 

Step 2: Boil the halved onions in water with 3 tablespoons of the vinegar until soft but not falling apart, about 15 minutes. 

Step 3: Put the chopped onions, carrots and celery in a food processor andblend until finely chopped. Combine the vegetable mixture, ground beef, oats, rice, tomato sauce, cold water, paprika, vegetable herb seasoning, chicken base, garlic and pepper in a bowl and mix well with your hands. 

Step 4: Remove the halved onions from the water and separate into cups. Fill each cup with meat mixture and place meat-side up in a single layer in a 12- by 15-inch baking pan. Mix the remaining 2 tablespoons vinegar with enough hot water to pour into the pan to cover halfway up the sides. Cover and bake for 2 hours. 

Step 5: To serve, transfer the stuffed onions to plates and cover with sauce. Serve with a cold sour cream and cucumber salad.