In a small bowl, whisk together the Greek yogurt, turmeric, garam masala, cumin, sea salt, and black pepper.
Toss the lean beef cubes in the yogurt mixture until well coated and let marinate for at least 30 minutes in the refrigerator.
Rinse the basmati rice under cold water until the water runs clear, then place in a small pot with 0.5 cups of water and the saffron threads.
Bring the rice to a boil, then reduce heat to low, cover, and simmer for 12-15 minutes until the water is absorbed and the rice is yellow and fluffy.
While the rice cooks, heat the ghee in a heavy-bottomed skillet over medium heat and sauté the sliced yellow onion until deeply caramelized.
Stir in the minced ginger and garlic, cooking for 1 minute until fragrant, then add the marinated beef and any remaining marinade to the pan.
Cover the skillet and simmer the beef on low heat for 15-20 minutes until tender and the sauce has thickened.
Spread the cooked saffron rice over the beef mixture in an even layer, sprinkle with chopped cilantro and mint, and cover for 5 minutes to steam through before serving.