Pat the chicken thigh fillets dry. Cut into strips about half an inch wide. Place in a bowl.
Lightly pound the black beans and garlic together.
Add the pounded black beans and garlic, fish sauce and pepper to the chicken. Mix well. Cover and allow to marinade while you prepare the rice.
Rinse the rice and place in a wide shallow cooking pan. Pour in 1 and 1/2 cups water. Bring to the boil. Cover the pan. Turn off the heat. Let the rice grains absorb the water in the residual heat for 10 minutes.
Toss the sliced Chinese sausages with the chicken.
Scatter the chicken (including the marinade) and sausage sliced over the rice.
Place the pan in a steamer set over simmering water. Cook for 30 minutes.
Off the heat, drizzle sesame seed oil over the steamed black beans and garlic chicken. Sprinkle in the scallions. Serve at once.