¼ cup plus 2 tablespoons hoisin sauce
2 tablespoons soy sauce
1 tablespoon brown sugar
1 ½ tablespoons water
1 ½ pounds flank steak, sliced very thinly against the grain on the bias into about 1 ½” strips
¼ cup (heaping) cornstarch
Vegetable oil (I like avocado or peanut), about 6 tablespoons total
2 teaspoons grated ginger
5 dried red chilis
2 teaspoons garlic, pressed through garlic press (about 4 large cloves)
4 green onions, sliced on the bias into 1” long pieces
Rice, to serve on the side, if desired
To prepare your sauce, whisk together the hoisin sauce, the soy sauce, the brown sugar and the water; set aside.
Toss the sliced flank steak with a couple of pinches of salt and black pepper, plus the the cornstarch; set aside while you heat your pan.
Place a wok, cast-iron skillet or other heavy-bottom pan over high heat, and drizzle in about 4 tablespoon of the oil; once smoking hot, add in some of the flank steak (working in batches) in an even layer and sear, undisturbed, on that first side for a couple of minutes; flip and sear on the other side, until the steak has a brown crust; remove and hold on a large plate, and repeat with the rest of the steak.
Reduce the heat under the pan to medium-low now (as it will be very hot), and add about 2 tablespoons more of the oil; then, add in the dried red chilis and stir to fry those up for about 30 seconds; then, add in the ginger and the garlic, and stir together for about 30 seconds until aromatic.
Add in the beef and stir to coat it in the mixture for about 30 seconds, then add in sliced green onions, and the sauce, and toss everything together to coat and become hot for about 30 seconds more.
Serve family style over a bed of white rice, or spoon onto a platter and serve separately with rice or noodles.