Preheat oven to 180 °C. Line a small baking tray with baking paper. Place pumpkin on the baking tray and spray with olive oil. Bake for 15-20 minutes or until pumpkin is cooked and golden brown. Set aside.
Bring vegetable stock and water to the boil in a medium saucepan over medium heat. Reduce heat and simmer, covered, until required.
Heat oil in a large saucepan over medium-high heat. Cook onion, zucchini, and asparagus stirring for 5-7 minutes or until softened.
Add rice and stir to coat. Reduce heat to low and add hot stock, a ladle or half a cup at a time, stirring continuously, until all the liquid has been absorbed. This process should take 20-25 minutes, and the rice should be tender and the risotto creamy.
While risotto is cooking, preheat a chargrill pan on medium-high heat. Brush chicken breast with olive oil and cook chicken for 5-8 minutes each side or until cooked through. Transfer chicken to a plate, and season with cracked pepper. Slice chicken breast.
To finish the risotto, add pumpkin and spinach and stir gently to combine until spinach has wilted.
To serve, divide risotto between 2 bowls and top with parmesan cheese. Place sliced chicken on top of risotto.