In a skillet, heat olive oil over medium heat. Add the sliced onions and a pinch of salt. Cook slowly, stirring occasionally, until the onions are caramelized and golden brown, about 15-20 minutes.

Prepare the Filling

In a bowl, combine the shredded short ribs, caramelized onions, provolone cheese, salt, and black pepper. Mix well to combine.

Assemble the Egg Rolls

Lay an egg roll wrapper on a clean surface with a corner facing you. Place about 2 tablespoons of the filling in the center. Brush the edges with beaten egg, fold the corner over the filling, and roll tightly. Seal the edges by pressing with your fingers. Repeat with the remaining wrappers and filling.

Fry the Egg Rolls

In a deep pot, heat vegetable oil to 350°F (175°C). Fry the egg rolls in batches until golden brown and crispy, about 3-4 minutes per side. Remove and drain on paper towels.

Serve

Serve the egg rolls hot with demi-glace and a dollop of horseradish cream on the side.