In a small saucepan, combine tamarind paste, honey, soy sauce, rice vinegar, garlic powder, and ginger powder. Cook over medium heat, stirring until well combined and slightly thickened. Season with salt and pepper to taste. Remove from heat and set aside.

Preheat a grill or grill pan over medium-high heat. Toss the trimmed spring onions with olive oil and season with salt. Grill the spring onions for about 3-4 minutes per side, until charred and tender. Remove from the grill and brush with the tamarind glaze. Set aside.

Pat the New York strip steaks dry with paper towels. Season both sides generously with smoked cumin, salt, and pepper. Heat vegetable oil in a skillet over high heat until just smoking. Add the steaks and sear for about 4-5 minutes on each side for medium-rare, or until desired doneness. Remove from skillet and let rest for 5 minutes.

In a mixing bowl, combine softened butter, mashed black garlic, mixed herbs, and salt. Use a hand mixer or fork to whip until smooth and well combined.

Slice the rested New York strip steaks against the grain. Serve the sliced steak with charred spring onions on the side, drizzled with any remaining tamarind glaze. Add a dollop of whipped black garlic and herb confit butter on top of the steak.