Cook the rice noodles according to package instructions, then drain and set aside.
In a small bowl, mix soy sauce, oyster sauce, hoisin sauce, brown sugar, and cornstarch until well combined.
Heat vegetable oil in a large skillet or wok over medium-high heat.
Add the sliced beef and stir-fry for about 3-4 minutes until browned.
Add garlic and ginger, cooking for an additional minute until fragrant.
Toss in the red bell pepper and snap peas, stir-frying for another 2-3 minutes until vegetables are tender-crisp.
Pour the sauce mixture over the beef and vegetables, stirring well to coat.
Add the cooked noodles to the skillet, tossing everything together until heated through and sticky.
Remove from heat and garnish with chopped green onions and sesame seeds if desired.
Serve immediately.