Preheat oven to 180˚C (160˚C fan forced). Season chicken with salt and pepper and place on an oven tray lined with baking paper. Drizzle with 1 tablespoon olive oil and roast for 50-55 minutes or until cooked through.
Remove from oven and stand for 15 minutes. Once cooled, discard skin, pull meat off bone and tear into bite size pieces.
Place cream, garlic and thyme in a small saucepan over medium heat. Bring to a simmer then turn off heat and let flavours infuse.
Blanch broccoli in a medium pot of salted boiling water for about 4 minutes, until just tender. Drain and set aside on paper towels to absorb any extra water.
Place broccoli in a food processor and pour in the cream mixture (discarding the thyme). Blend until smooth. Season to taste with salt and pepper.
Bring a large saucepan of salted water to the boil and cook pasta until al dente, about 13 minutes, or according to packet instructions.
Place a large non-stick frying pan over high heat and add remaining oil. Once very hot, brown the mushrooms for 4 minutes. Reduce heat, add onion and cook for 3 minutes until softened. Season with salt and pepper.
Add chicken and cook for 3-4 minutes until reheated. Pour broccoli sauce over chicken and toss to combine.
Drain pasta and add to frying pan. Carefully combine and pour onto serving platter. Garnish with parmesan and serve immediately.
Notes: Prep Time 15 minutes Cook Time 1 hour 20 minutes