Rice – How much does a a cup of rice weigh

There shouldn't need to be any variation in the water at all, since the things that you are adding are already hydrated and are not taking in any water. Indeed, it would be possible that some vegetables might even give off water.

I would be more inclined to look to whether you are measuring accurately every time you use the rice cooker (just asking) and then, if so, whether your rice cooker is consistent. I had an inexpensive rice cooker that I liked for the convenience, but it was inconsistent on turning off, so the results were a little too varied, OK for me, but not when I was serving other people.

The only other thing to consider is that many rice cookers work on a temperature principle...when the temperature starts to rise (meaning the water has been absorbed) the cooker shuts off. If the ingredients you are adding are raising the temperature of boiling (as in a lot of salt, say) then it is possible that you cooker is shutting off before the rice is cooked, and then the water is absorbed or evaporates, but the rice cooks no further.

I would pay very close attention to your measuring (rice and water) for the next couple of batches and see if that fixes the problem.

This is something that really puzzled me when I went living in an English-speaking country. Having grown up in Italy, where recipes tell you "Put 120g of this then add 250g of that", I've always used a scale. The first time I saw I recipe with cups and teaspoons I said: yeah, but I've got 10 types of cups in the kitchen... which one should I be using?

Then someone told me that they were real unit of measure and introduced me to measuring spoons (something that in Italy would be very difficult to come by).

So, going back to your question:

1. I strongly second @Adam's opinion of buying a digital scale: they're cheap and do the job (personally, I would not spend more than $30-40 on it, but you can find $300 ones if you wish).

2. If your recipe calls for teaspoons, cups, etc. then you can:

   • Buy measuring spoons/cups (you can find a complete set for $10, for instance this)

   • Convert them to g (or whatever your scale measures) using an online calculator. If you google for "teaspoons to grams" or "cups to grams" you'll find plenty.

You can even get an app on your phone. I use this app which works pretty well (I'm sure there's a similar thing for iPhone, but I don't use Apple products, so I can't help there).