Yet another Kitchen Kalamity.
I knew that you weren't supposed to put Pyrex in the oven until it had preheated. I didn't know why, but I knew that was the case. So I was very careful to defy the recipe and wait until the oven was preheated to put my steam pan on the bottom shelf of my oven. After two hours of folding, rolling, and waiting for my baguette to rise, I was ready for some delicious homemade bread to take to Cannon Beach!
I've made this recipe before. But I've used a cast iron skillet as my steam pan. This makes the pan get a little rusty. I thought that, since the Pyrex pan was the same width and length as my cookie sheet, it would make the steam distribute more easily. (There really was thought in this!)
It was when I poured the water into the steam pan that disaster struck. The pan exploded, and something tells me that even if I had used warm water, the pan still would have exploded.
But the disaster was minimally disastrous. I had never used that pan before, so it won't be missed. The glass stayed mainly in the oven. None flew directly at me. The oven itself isn't damaged. The bread even looks fine; since it was still uncooked dough, it would be easy to see if any glass shards landed in it, but they did not. (It's wrapped up now and will live in the fridge until I get back to Portland.) However, this is your cue, more experienced bakers who read this blog, to warn me if baking that most-likely-glass-free baguette tomorrow is a bad idea. Right now the oven is open so it will cool off faster. I think no good would come of trying to sweep out a hot oven of hot, potentially volatile pieces of glass.
I think I'm just going to invest in a second cookie sheet to use as a steam pan.