Prep all of your ingredients.

Heat 1 Tbsp peanut oil in a small sauce-pot over medium-low heat. Add the onion whites and saute until just starting to turn brown.

Add the ginger and garlic and sauté until soft and fragrant, about 2 minutes.

Add the soy sauce and water, stirring to combine.

Stir in the brown sugar along with a few shakes of sesame oil and increase the heat to medium. Bring the sauce to a boil for 3 minutes. Remove the sauce from the heat and set aside.

Place the cut-up steak into a large bowl and sprinkle with kosher salt and cracked pepper. Toss the steak and then add a little more salt and pepper.

Next add the cornstarch and toss to thoroughly cover the pieces of meat. Allow the steak to sit for 10 minutes to set the corn starch.

Place a large sauté pan or wok over medium-high heat and add 1/2 cup peanut oil. Once the oil is hot (but not smoking), add the beef to the pan in 1 cup increments and sauté for 2 minutes until it is seared on all sides but barely cooked in the center. Remove the steak from the pan with a slotted spoon and transfer it onto a bowl.

When the meat is all browned, place the sauté pan or wok back over medium heat. Add the prepared sauce to the hot pan (it should come to a boil almost immediately), then add the reserved steak and cook at a boil, stirring constantly for 2 minutes.

Transfer the steak and sauce to a bowl.

Serve over rice and garnish with the onion greens and sesame seeds.