In a bowl, combine the corned beef, Swiss cheese, sauerkraut, and thousand island dressing. Mix everything together until well combined. Taste and adjust the seasoning with salt and pepper as needed.
2. Assemble the egg rolls:
Lay an egg roll wrapper flat on a clean surface, with one corner pointing toward you (like a diamond shape).
Spoon about 2-3 tablespoons of the filling mixture into the center of the wrapper.
Fold the bottom corner over the filling, then fold in the sides, and roll it tightly to form a cigar shape. Seal the edge with a little bit of the beaten egg to keep it closed.
3. Cook the egg rolls:
Option 1: Frying:
Heat about 2 inches of oil in a large skillet over medium-high heat (or use a deep fryer if you have one). Once the oil is hot (around 350°F or 175°C), carefully add the egg rolls to the skillet, a few at a time, being careful not to overcrowd the pan.
Fry the egg rolls for 3-4 minutes, turning occasionally, until golden brown and crispy. Once done, remove from the oil and place them on a paper towel-lined plate to drain any excess oil.
Option 2: Baking:
Preheat your oven to 400°F (200°C). Brush the egg rolls with olive oil or vegetable oil and place them on a baking sheet in a single layer.
Bake for 15-20 minutes, flipping halfway through, until they are golden brown and crispy.
4. Serve:
Serve the Reuben egg rolls hot, with extra thousand island dressing on the side for dipping.
