Beef Rouladen with Bacon, Onion and Mustard

Lay the beef slices flat on a work surface. Season both sides generously with salt and black pepper.

Spread 1 tablespoon of mustard evenly across each slice, covering the entire surface.

Distribute the diced onion and lay 1-2 bacon strips along the center of each slice.

Roll each slice tightly into a log, pressing gently to compress the filling. Secure each end with toothpicks if needed.

In a heavy casserole or Dutch oven, melt butter over high heat until it foams and begins to turn golden.

In a heavy casserole or Dutch oven, heat 1-2 tbsp neutral oil (such as vegetable or canola) over high heat until shimmering. Add butter only after searing begins, allowing it to foam without burning.

Reduce heat to medium. Add the sliced onion and carrot to the same pot. Cook, stirring occasionally, until softened and lightly golden, about 5 minutes.

Add the minced garlic and cook for 1 minute until fragrant.

Pour in the tomato sauce and white vinegar. Stir to combine, scraping up the fond from the bottom of the pot.

Nestle the seared beef rolls into the sauce, ensuring they are mostly submerged. Bring to a gentle simmer.

Cover the pot and reduce heat to low. Braise for 2 hours until the beef is completely tender and yields easily to a fork.

Check every 30 minutes, giving the pot a gentle shake. If the sauce reduces too aggressively, add a splash of water only as needed.

Remove the beef rolls carefully. Strain the braising sauce through a fine sieve, pressing the vegetables to extract all liquid. Return sauce to pot.

Reduce the sauce over medium-high heat for 5 minutes until it coats the back of a spoon nicely. Taste and adjust seasoning with salt and black pepper.

Slice each beef roll on the bias into 3-4 rounds. Fan the slices on warm plates and nap generously with the reduced sauce.

Finish with a generous sprinkle of fresh parsley. Serve with buttered potatoes or warm spaetzle alongside.