Wash the rice until the water runs clear. Add water to the rice and bring to a boil. Once boiling, cover and lower the heat to a low heat. Cook until the rice has soaked up all the water. Keep covered and remove from the heat. Allow the rice to steam until the beef stir fry is ready.
Meanwhile, slice the beef into thin pieces and add to a medium bowl. Add oil, soy sauce, dark soy sauce, rice vinegar, sesame oil, honey, oyster sauce, salt, water, cornstarch, and baking soda. Mix and allow to marinade while you cut the vegetables.
Remove the core from the green pepper and cut into large chunks. Remove the onions top and bottom and cut into wedges. Remove the roots of the spring onion and slice lengtheise and then in 5 cm pieces. Keep the white and greener part of the spring onion separate and you'll only be adding the greener (top part) towards the end.
Bring a large non-stick saucepan or wok to a medium-high heat. Add 1 tbsp oil and the marinaded beef with all its sauce. Fry for 3-5 minutes or until the beef starts to caramelize. Remove the beef from the pan and set aside.
In the same pan, on a medium-high heat, add 2 tbsp oil and kale, green pepper, onion and the white parts of the spring onion. Sauté for 3-5 minutes or until the vegetables start to charr but still have a bite to them.
Add the beef and remaining spring onion to the vegetables and sauté for 30 seconds. Remove from the heat.
Serve the beef stir fry on a bed of rice and top with toasted sesame. Enjoy, tastebud!