In skillet or wok, saute onion, garlic, ginger, turmeric, cardamom and lemongrass in both oils. Cover and cook over low heat for 20 minutes. Uncover and add chicken and sesame seeds. When chicken is well browned, sprinkle in flour and pour in coconut milk. Simmer uncovered until chicken is cook and the broth is thickened about 30 minutes. Soak noodles in water for 10 minutes. Place on stove over high heat. As soon as the water is hot but not boiling the noodles are done. Drain in cold water. Arrange noodles in bowl and pour curry over. This will reheat the noodles.