Step 1: Prepare your ingredients. Mince the garlic and ginger. Slice the green onions, separating the white and green parts. In a small bowl, whisk together the soy sauce, water, brown sugar, sesame oil, and cornstarch. Set aside. Cook your rice noodles according to package directions, typically by soaking in hot water for 5-7 minutes until tender, then drain and set aside. Don’t overcook them; they’ll continue to soften slightly when mixed with the hot sauce.
Step 2: Heat a large skillet or wok over medium-high heat. Add a tablespoon of vegetable oil. Once hot, add the ground beef, breaking it up with a spoon. Cook until browned and crumbled, about 5-7 minutes. Drain any excess grease.
Step 3: Add the minced garlic, ginger, and the white parts of the green onions to the browned beef. Sauté for 1-2 minutes until fragrant, being careful not to burn the garlic. This aromatic base is key to delicious Mongolian Ground Beef Rice Noodles.
Step 4: Give your prepared sauce a quick whisk again (cornstarch tends to settle) and pour it over the beef mixture in the skillet. Bring to a gentle simmer, stirring constantly, until the sauce thickens and becomes glossy, about 2-3 minutes. It should coat the back of a spoon.
Step 5: Add the drained rice noodles to the skillet with the beef and sauce. Toss everything gently to ensure the noodles are evenly coated in the rich Mongolian sauce. Cook for another 1-2 minutes, allowing the noodles to absorb the flavors.
Step 6: Remove from heat. Stir in the green parts of the green onions. Taste and adjust seasoning if necessary. Serve immediately.