Boil the rice until half cooked, rinse it with cold water and set it aside.
In a large non stick pan heat the butter and olive oil and saute the garlic and onion until lightly golden.
Then add the mushrooms, sweet peas and saute until the mushrooms are soft.
Blanch the broccoli and carrots and add to the pan.
Add the rice and the chicken stock and stir until the rice absorbs all the chicken stock.
Season the risotto with salt and pepper, and if the rice is not completely cooked, add some more stock and keep cooking for a little while longer.
If desired, you can add a teaspoon of good quality oyster sauce to the risotto.
Finally put the grated Parmesan cheese into the risotto in the last moment before removing the pan from the heat.