Before you start, bring a medium pot of salted water to the boil. Preheat BBQ to medium-high (if using).
Cook rice in boiling water for 20-25 minutes, until tender. Drain, return to pot and keep warm.
Prep broccolini and courgette.
Prep ginger and garlic. Pat beef dry and toss in a large bowl with ginger, garlic and soy sauce. Set aside to marinate.
Heat a large, dry fry-pan on medium heat. Add sesame seeds and toast for about 2 minutes, stirring often, until golden. Remove from heat (reserve pan) and transfer to a small bowl. Prep coriander and mint and add to bowl along with vinegar, soy sauce and oil. Mix and season to taste with salt and pepper.
Return reserved pan to medium-high heat with sesame oil. Cook beef for about 4 minutes each side for medium (depending on thickness), or until cooked to your liking. Reserve pan. Rest, covered, before slicing thinly and tossing back through any resting juices. Alternatively, cook beef on the BBQ.
Wipe pan clean and return to medium-high heat. Add broccolini, courgette and a splash of water and cook for about 4 minutes, until tender. Remove from heat, stir through spinach and soy sauce and season to taste with salt and pepper.
Serve rice with greens and beef. Drizzle over chimichurri.