Lay the beef slices flat on a clean surface. Season with salt and pepper.
Place a small handful of enoki mushrooms at one end of each beef slice. Roll the beef around the mushrooms tightly and secure with a toothpick if necessary.
In a small bowl, mix together soy sauce, sesame oil, garlic, and ginger.
Heat vegetable oil in a large skillet over medium-high heat. Add the beef rolls seam side down and cook for about 3-4 minutes, turning occasionally, until browned and cooked through.
Pour the soy sauce mixture over the beef rolls in the skillet and cook for an additional 1-2 minutes, allowing the sauce to coat the rolls.
Remove from heat and garnish with sliced green onions before serving.