In a medium bowl, whisk together soy sauce, sesame oil, brown sugar, minced garlic, and grated ginger until well combined. Place the flank steak in the marinade, ensuring it's fully coated. Cover the bowl and refrigerate for at least 30 minutes.

Cook jasmine rice according to package instructions, usually bringing water to a boil, adding rice, and simmering for about 15 minutes until tender. Once cooked, fluff the rice with a fork and set aside.

In a small bowl, mix sour cream, Sriracha, lime juice, honey, and a pinch of salt and pepper. Whisk until smooth and creamy, adjusting the Sriracha to your desired spice level.

Heat a grill pan or skillet over high heat. Remove the marinated flank steak from the fridge and sear it for 5-6 minutes on each side until it reaches 130°F for medium-rare. Allow it to rest for at least 5 minutes before slicing.

In the same pan, reduce heat to medium-high and add vegetable oil. Once shimmering, toss in mixed vegetables and sauté for 5-7 minutes until they’re tender-crisp.

Divide the fluffy jasmine rice among serving bowls, layer with thinly sliced steak and sautéed vegetables. Drizzle generously with the spicy cream sauce.

To garnish, sprinkle sesame seeds and chopped green onions on top.