CorningWare, Pyrex, Anchor or other glass casserole or baking dish. Glass bakeware absorbs, rather than reflects, heat. It conducts and retains heat more than metal. These features speed up the cooking process. Because of this, you should turn your oven 25 degrees lower than the recipe recommends to avoid burning. Since food cooks in the same amount of time in glassware as in metal pans, you will save a few cents in energy costs each time you bake. Much like dark metal, it absorbs heat, making it ideal for crisp-crusted pies but much less so for bar cookies, quick breads, and fruit crisps, which can easily become burnt.
You can watch your food cooking if you are using clear glassware.
Glassware is a perfect vessel for micro-cooking as well as baking in the oven.
(however, it is not so great for stovetop cooking)
You can freeze, refrigerate, bake and serve in the same dish.
Glass is inert, meaning that there are no chemicals to leach out into the food (and to you) as there is with
plastics and even some metals (for example, cast iron leaches iron into foods). There are also no reactions with foods, such as acids.
Glassware does not stain and is generally easy to clean; they are dishwasher safe.