1. Rinse the rice: Wash the rice under cold water until the water runs almost clear. Drain thoroughly. (See “How to Wash Rice the Japanese Way” for details.)
2. Prepare the chicken and onion: Finely dice the onion. Cut the chicken thighs into bite-sized pieces.
3. Assemble in the rice cooker: Add the rinsed and drained rice to the rice cooker pot. Add ketchup, Worcestershire sauce, soy sauce, consommé, salt, and pepper. Add water until it just reaches slightly below the 2-cup line on your rice cooker (approximately 300 ml). Mix well to combine.
4. Add the toppings: Scatter the diced onion and chicken pieces over the top of the rice mixture. Do not stir.
5. Cook the rice: Close the lid and set your rice cooker to the white rice (standard) setting.
6. Add the finishing touches: Once the rice is cooked, open the lid and add the frozen vegetables and butter. Close the lid and let the residual heat warm the vegetables and melt the butter (about 5–10 minutes).
7. Mix and serve: Use a rice paddle to mix the rice, using a slicing motion to fluff and combine the ingredients. Serve immediately or use the rice as a filling for homestyle omurice or top with a soft scramble. 

To Cook on the Stove

1. Follow steps 1-4. Then place the pot on the stove over medium heat and bring the mixture to a gentle boil. Once it begins to boil, reduce the heat to the lowest setting, cover with the lid, and let it simmer for about 15–20 minutes, or until the rice absorbs all the liquid. Resume to steps 6-7.