Rouladen, a Christmas Eve Tradition | Kitchen Frau

Name: Rouladen, a Christmas Eve Tradition | Kitchen Frau
Cuisine: European, German
Ingredients: For each roulade; 1 thin slice from a beef roast (the inside round works well); about 2 teaspoons Dijon mustard; 2 slices bacon; 4 lengthwise pickle slices, cut into long strips; ¼ cup (60ml) chopped onion; toothpicks or cotton kitchen string; 1 tablespoon olive oil; about 1 cup (240ml) red wine; 2 bay leaves; 5 juniper berries or 2 whole cloves; water to cover; salt and pepper to taste; flour, sweet rice flour, or cornstarch for thickening