1. Heat the vegetable oil in a large skillet over medium-high heat. Add the ground beef and cook until browned, breaking it apart with a wooden spoon, about 5-7 minutes. Drain any excess fat.
2. Add the minced garlic and grated ginger to the skillet with the beef. Cook for an additional 1-2 minutes until fragrant. This step always reminds me of early mornings spent sneaking into the kitchen, the aroma of garlic and ginger coaxing me awake.
3. In a small bowl, mix the soy sauce, brown sugar, and red pepper flakes. Pour the mixture over the beef, stirring to combine.
4. In another small bowl, dissolve the cornstarch in water and add it to the skillet. Stir well and let the sauce simmer until it thickens slightly, about 3 minutes.
5. Add the green beans to the skillet and cook until they are tender-crisp, about 3-4 minutes. The vibrant green of the beans against the rich sauce is a sight that always brings a smile to my face, much like the colorful dishes my mum would prepare.
6. Stir in the sliced green onions, then season with salt and pepper to taste.
7. Serve the ground beef Mongolian beef over cooked rice, garnished with additional green onions if desired.

Each step is a dance of flavors coming together, much like the lively gatherings around our family table. Don’t rush the process; let the aromas fill your kitchen and transport you to a place of culinary comfort.