Tip the rice into a large bowl. Cover with cold water and whisk for 1-2 mins till the water goes cloudy (this is the starch). Drain, rinse under cold water and tip back into the bowl. Cover with fresh water and set aside.
Prepare your veg for the stir-fry: peel and finely slice the onion. Trim the ends off the carrot and peel it. Slice it into fingerlength batons. Break the broccoli into small florets and roughly chop the stalk. Peel and grate the garlic and ginger.
Put a deep frying pan or wok over a medium heat. Tip in the sesame seeds. Toast for 3-4 mins till golden and popping, shaking the pan. Tip into a bowl and set aside for later.
Turn the heat up under the wok. Add 1 tbsp oil and the beef stir-fry strips. Stir fry for 6-8 mins till browned all over. Lift out of the wok and place in a bowl for later.
While the beef cooks, drain the rice. Tip it into a small pan. Pour in 400 ml boiling water and add a pinch of salt. Cover and put on a high heat. Bring to the boil, then turn the heat right down. Gently cook over a low heat for 8 mins till all the water is absorbed. Take off the heat and set aside, lid on, to finish cooking.
Add the onion, carrot and broccoli to the empty wok with a splash of water. Stir fry for 5-8 mins till the veg have softened a little and look a little glossy. Stir in the garlic and ginger. Return the beef to the pan.
Pour the tamari into the pan. Add 150ml boiling water. Let it bubble up and simmer for 2-3 mins to just mingle the flavours.
Fluff up the rice with a fork. Divide between 2 warm bowls. Top with the sesame beef stir-fry and sprinkle over the toasted sesame seeds to serve.