Commonly used for lasagna, I use a pyrex baking pan for both baking bar cookies and setting caramels. Newer models come with a lid to seal and protect your food. Although I have several baking pans to accommodate multiple batches of caramel in an evening, my favorite pan is a really old one that is a little flatter with shorter, vertical sides. Most new pans have taller angled sides, which still works fine.
Some metal broiler pans (not the louvered ones that come with an oven) also work fine for caramels, but I would stick to glass for baking. The glass absorbs heat more slowly and let's you see if the bottom is browning.
