Heat the oil in a large pot over medium heat, add the onions, and sauté for 15 minutes until golden brown. Add garlic, turmeric, mint flakes, salt, and pepper, and stir-fry for 20 seconds. Add the mung beans and broth, and bring to a boil. Reduce heat to medium, cover, and simmer for 15 minutes, stirring occasionally. Add the walnuts and bulgur, bring back to a boil, red