First, before you attempt this recipe. Pyrex DOES NOT go on top of the stove. It is to be used in the oven or microwave. Having said that, there are some Pyrex-like products that are made by Corning that can be used on top of the stove. If your baking dish says "Pyrex" on it, use it only as I said first.
As for the rice, I can only surmise that the rice would be put in the pan with what other ingredients called for and would be covered tightly with foil. The foil would keep the moisture inside and would essentially produce steam, which would result in "steamed" rice. However, without knowing more about the recipe, I'm only guessing.