Step 2

Melt 2 tbsp butter in a heavy skillet over medium heat. Sauté the onion and rutabaga for 5 minutes until the onion is soft.

Step 3

Finely mince or grind the beef brisket together with the sautéed onion and rutabaga. Melt the remaining 4 tbsp butter in the pan over medium heat, add the meat mixture and cook over low heat, stirring occasionally, until all moisture has evaporated and the mixture is firm enough to hold its shape.

Step 4

Remove from heat, cool, then stir in 1 beaten egg. Season well with 1 tsp salt and black pepper.

Step 5

Preheat the oven to 175°C / 350°F. On a lightly floured surface, roll the chilled dough into a 33×20cm (13×8 inch) rectangle about 3mm thick.

Step 6

Spoon the filling down the centre lengthwise, leaving 2.5cm free at each end. Brush the long edges with cold water, fold one side over the filling, then fold the other side over the top. Brush the short ends with water and fold them over to seal.

Step 7

Place seam-side down on a baking sheet. Brush the top with the remaining beaten egg. Bake for 30 minutes until deep golden brown.

Step 8

Slice diagonally into 4cm pieces and serve as an appetiser or alongside soup.