1. Bring a large pot of salted water to a boil. Place the steak, soy sauce, sesame oil, chili sauce, honey and fresh ginger in a ziplock freezer bag. Close the bag and turn it to coat the steak with the marinade. Marinate at room temperature 15 minutes.
2. Add the potatoes to the boiling water. Cook until fork tender, about 10 minutes. Drain fully and return to pot. Pour in the almond milk and mash until smooth. Gently fold in the yogurt and add the ground ginger, wasabi paste and salt.
3. Meanwhile, heat a large pan over medium heat. Add 2 tablespoons of the marinade, then the steak, to the pan. Sear steak 3 to 5 minutes on each side. Remove to a cutting board and let rest 5 minutes.
4. Slice steak into 1/4-inch-thick pieces. Serve with mashed potatoes.