Preheat oven to 200˚C, fan on.
Add your mushroom mix to a large mixing bowl. Drizzle over the olive oil, balsamic vinegar, soy sauce, garlic and oregano. Season with some black pepper as the soy is salty. Toss well, coating every piece of mushroom in the seasoning.
Place on a large baking tray, well-spaced out. Roast for ± 7 minutes until just tender and juicy
When done, keep mushrooms on the roasting tray and keep the mushroom roasting liquid that will have been released while cooking. This will form a delicious dressing.
While the mushrooms are roasting, bring a pot of salted water to the boil. Blanch the broccoli and then the green beans until bright green and just cooked through.
Using tongs, drain the veg and place the min a large mixing bowl. Add the lemon zest and the juice of half the lemon. Season with salt and pepper. Mix to dress the beans and broccoli all over.