Pull-apart sandwiches with French onions and roast beef

Ingredients:

Refueling

• 0.5 cup mayonnaise
• 1/4 cup chopped pickles
• 2 tbsp. ketchup
• 1 tbsp horseradish
• 0.5 tsp. dried dill
• 1/4 tsp onion powder
• A little hot sauce

Sandwiches

• 6 tablespoons unsalted butter
• 2 large sweet onions, thinly sliced
• 2 tsp chopped fresh thyme
• 2 tbsp. l. dry sherry
• 1 cup lightly salted beef broth
• 1 tbsp Worcestershire sauce
• 1 oval loaf of rye bread, 15 cm in size.
• 350 g thin slices of roast beef
• 170 g of grated Swiss cheese

Preparation:

1. Prepare the dressing:
   
   In a small bowl, combine mayonnaise, pickles, ketchup, horseradish, dill, onion powder, and hot sauce; season with salt to taste. Cover and refrigerate.
2. Preheat oven to 220°C. Line a baking sheet with parchment paper.
3. Make sandwiches:
   
   Melt the butter in a large skillet over medium heat. Pour 4 tablespoons of butter into a small bowl and set aside. Add the onion and thyme to the skillet with the remaining butter and cook, stirring occasionally, until dark golden brown, 12-15 minutes.
4. Add the sherry to the pan and cook until reduced. Add the beef broth and Worcestershire sauce and bring back to a simmer. Cook until the liquid is reduced by half and the onions are caramelized, 2-3 minutes. Season with salt and pepper to taste.
5. Trim the ends of the loaf. Cut the bread diagonally into 12 slices, without cutting all the way through the bottom. You can place chopsticks along the long sides of the bread to avoid cutting all the way through. Transfer to a baking sheet.
6. Brush the entire loaf and the slits with the reserved melted butter. Set aside about a third of the onion. Fill every other slit of the bread with the remaining onion, starting with the first slit. Fold the roast beef slices in half and insert them into the slits filled with onion along with the cheese. Sprinkle the loaf with the reserved onion and drizzle with the onion juices.
7. Bake until the cheese is golden brown and bubbly, about 20 minutes. Tear into sandwiches or cut the loaf into sandwiches. Serve with the dressing.