I am not very good at specifying exact amounts because I tend to measure by "eye", but anyway, this isn’t exactly a difficult recipe that requires preciseness.
I cook practically everything in my wok but this could also be cooked in a deep frying pan and maybe better would be a saucepan.
First heat the oil in whatever pan you choose to cook this in. Add the chopped onion and garlic. Fry lightly until soft. Add the rice and fry for a minute or two before adding the mushroom and pumpkin. Stir it occasionally. Let that fry for another couple of minutes until the mushroom is soft.
There are two ways to do this but both ways seem to work. The first is the lazy way: add all of the stock, stir it, put a lid on and walk away (coming back to check and stir occasionally). It is ready when the rice is cooked and the stock has been absorbed. The problem with this is that sometimes the rice can be overcooked if the amount of stock is too much (and it always changes).
The second way is to add 1/2 cup of stock at a time, stirring almost continuously and adding more stock as soon as the previous has been absorbed. It generally takes about 20 minutes.
When it is cooked it should be sort of creamy and the pumpkin should have separated and mushed into the rice. Add some pepper for a bit more flavour and serve.
I made this the other night and served with chilli herb grilled veggies (potato, sweet potato, capsicum and squash) -my chilli herb grilled veggies are like what restaurants call a vegetable stack.