In a bowl or measuring cup, make the Mongolian sauce by whisking together soy sauce, brown sugar, hoisin sauce, low-sodium beef broth, sesame oil, red pepper flakes, and corn starch until smooth and set aside.
¼ cup soy sauce, 2.5 Tbsp brown sugar, 2.5 Tbsp hoisin sauce, ⅓ cup low-sodium beef broth, ½ tsp sesame oil, ½ tsp red pepper flakes, 1 Tbsp corn starch
Heat the neutral oil in a large skillet over medium-high heat. Add the ground beef, break it up with a spatula, and cook until browned and cooked through, about 2-3 minutes.
1 Tbsp neutral oil, 1 pound ground beef
Add the garlic, ginger, and chopped green onions to the skillet and cook for about 30–60 seconds, until fragrant and slightly softened.
3 cloves garlic, 1 Tbsp minced ginger, 2 green onions
Pour in the prepared sauce and stir to coat the beef evenly. Bring to a simmer and cook for a few minutes, stirring frequently, until the sauce thickens and becomes glossy.
Taste and adjust with salt as needed, then remove from heat and garnish with sesame seeds and more chopped green onions. Serve with rice and veggies.
Salt, Sesame seeds, Chopped green onions