My recent habit has been to make a tomato sauce with fermented green chiles and then poach an egg in it, via a small clay cazuela. I've been using my Mexican clay and it's been working like a charm. Plus, it's a delicious way to start the day. I know that not everyone has a Mexican clay mini-cazuela (what kind of world do we live in that this has to be true?) so I thought I'd practice with one of my Spanish cazuelas. I've always thought that if the clay were dark and muddy, it should be fine but if it breaks and the inside looks like porcelean, it's only for low oven cooking, not direct heat. Well, I was wrong! These Spanish cazuelas are not for direct heat. I used a very low flame and the next thing you know, crack! I'm not upset as I have many of these and many more Mexican pieces but I thought it was interesting to note. And for good measure, here's a Mexican mini-cazuela with a poached egg in tomato sauce a few minutes off the heat. It's still bubbling and still in one piece! We'll have to look into importing these. They're very handy and cute, too.