Prepare the Tempeh: First, cut each block of tempeh into bite-sized cubes, about 2cm wide. Bring a small pot of water to the boil, then drop in the tempeh cubes. Simmer for 5 minutes. This step removes any natural bitterness and opens up the tempeh's pores, allowing it to absorb more sauce. You'll notice a faint, nutty aroma rising from the pot. Drain the tempeh well and pat it thoroughly dry with a clean tea towel.

Make the Sauce: In a small bowl, whisk together the soy sauce, maple syrup, rice vinegar, and sesame oil. Set this aside. In a separate, larger bowl, toss the dried tempeh cubes with the cornflour until they are evenly and lightly coated. The tempeh will look a little dusty and pale.

Crisp the Tempeh: Heat 2 tablespoons of the oil in a large frying pan or wok over a medium-high heat. Once the oil is shimmering and you see a wisp of smoke, carefully add the tempeh cubes in a single layer. Do not overcrowd the pan; cook in two batches if needed. Let the tempeh cook undisturbed for 3-4 minutes. You'll hear a satisfying sizzle. When the underside is a deep golden brown and feels firm to the touch, flip each cube. Cook for another 3-4 minutes until all sides are crispy and beautifully browned. Remove the tempeh from the pan and set it aside on a plate.

Stir-Fry the Vegetables: Reduce the heat to medium and add the remaining tablespoon of oil to the pan. Add the sliced onion and cook for 2-3 minutes, stirring often, until it softens and turns translucent. The aroma will become sweet and fragrant. Add the minced garlic and grated ginger, cooking for a further 30-60 seconds until they release their scent, taking care not to burn them.

Add the Remaining Veg: Toss in the sliced bell pepper, tenderstem broccoli, and mangetout. Stir-fry for 4-5 minutes. The broccoli should turn a vibrant, bright green and the peppers will soften slightly but still have a pleasant crunch. You'll hear the vegetables hissing and popping as they cook.

Combine and Glaze: Return the crispy tempeh to the pan with the vegetables. Pour the prepared sauce over everything. Toss vigorously for 1-2 minutes, allowing the sauce to bubble, reduce slightly, and glaze all the ingredients. The sauce will thicken and cling to the tempeh and vegetables, creating a glossy, appetising sheen.

Finish and Serve: Remove the pan from the heat. Sprinkle the sliced spring onions over the top. Serve immediately over a bed of fluffy brown rice or your favourite noodles. The contrast between the crispy tempeh, tender vegetables, and sticky sauce is absolutely wonderful.