01 -
Preheat the oven to 180°C. Using a meat mallet or rolling pin, pound the beef slices to approximately 0.6 cm thickness. Season both sides with salt and black pepper.
02 -
Spread a thin layer of mustard over each beef slice. Lay one slice of prosciutto or two slices of bacon on top, then distribute pickle spears, sliced onions, and a little chopped parsley evenly over each.
03 -
Fold in the long sides of each steak, then roll tightly from the short end. Secure each roulade with toothpicks or kitchen twine. Lightly dredge the rouladen in flour.
04 -
Heat oil and butter in a large heavy-based saucepan or Dutch oven over medium-high heat. Brown the rouladen on all sides until deeply coloured, then transfer to a plate.
05 -
Add an additional tablespoon of butter to the pan. Sauté carrots, parsnips, celeriac, and leek for about 10 minutes until softened. Stir in tomato paste and sugar; cook for 2 minutes.
06 -
Add red wine and beef stock, scraping any browned bits from the bottom. Bring to a simmer, stirring to combine.
07 -
Nestle the rouladen into the sauce so they are partially submerged. Cover with a tight-fitting lid and transfer to the oven. Cook for 90 minutes.
08 -
After 45 minutes, carefully turn the rouladen. Continue braising for the remaining time. Check for tenderness after 90 minutes; if necessary, cook an additional 20 minutes.
09 -
Remove toothpicks or string before serving. Arrange rouladen on plates and spoon over ample sauce with vegetables. Accompany with spätzle, potatoes, or crusty white bread.