In a medium bowl, whisk together soy sauce, fresh ginger, minced garlic, honey, rice vinegar, and sesame oil until well combined. Place the hanger steak in the mixture, ensuring it’s fully coated. Let it marinate for at least 30 minutes.

Heat a skillet over medium-high heat and add a splash of vegetable oil. Remove the steak from the marinade, letting excess liquid drip off.

Carefully place the marinated hanger steak in the hot skillet. Sear for 4-5 minutes without moving, then flip and cook for an additional 4-5 minutes for medium-rare doneness. Transfer to a cutting board to rest.

In the same skillet, add another tablespoon of vegetable oil followed by the mixed vegetables. Stir-fry for 3-4 minutes until bright and crisp-tender. Add red pepper flakes if desired.

After resting for about 5 minutes, slice the steak against the grain into thin strips. Serve alongside the stir-fried vegetables and drizzle with remaining juices.