Preheat your oven to 190°C (170°C fan). Grease a medium-sized baking dish (roughly 20cm x 25cm) with a knob of butter. The butter will melt and coat the dish, ensuring nothing sticks and adding a subtle richness to the edges.

Steam the broccoli until just tender. Place the florets in a microwave-safe bowl with a splash of water, cover, and microwave for 2-3 minutes, or steam them in a pan for 3 minutes. You want them bright green and still with a slight crunch—they will cook further in the oven. Drain well and set aside.

Make the creamy sauce. In a large mixing bowl, combine the cream of mushroom soup, mayonnaise, curry powder, lemon juice, and chicken stock. Whisk until the mixture is smooth and pale yellow in colour. The aroma will be tangy from the lemon and warm from the curry powder, without being overpowering.

Combine the chicken and sauce. Add the raw chicken pieces to the bowl with the sauce. Stir well so every piece is coated. The chicken should look glossy and evenly covered in the creamy mixture.

Assemble the casserole. Spread the steamed broccoli evenly across the bottom of the greased baking dish. Then, pour the chicken and sauce mixture over the top, spreading it out so it covers the broccoli completely. The dish will look quite full, but that's fine.

Top with cheese and breadcrumbs. Sprinkle the grated cheddar cheese evenly over the top, followed by the fresh breadcrumbs. Give the dish a gentle shake to settle everything. The surface should now be a patchwork of golden cheese and pale crumbs.

Bake until bubbly and golden. Place the dish in the preheated oven and bake for 25-30 minutes. You'll know it's ready when the sauce is bubbling vigorously around the edges, the chicken is cooked through (check a piece is no longer pink inside), and the top is a deep golden brown and crisp to the touch. The smell of curry, chicken, and melted cheese filling your kitchen is the final cue.

Rest before serving. Remove the dish from the oven and let it sit for 5 minutes. This allows the sauce to thicken slightly and makes serving much easier. The top should still be crunchy, but the filling underneath will be piping hot.