Though I took delivery of a new oven a little over a month ago, I haven't put it through all of its paces yet. The biggest reason for this has been the lingering hot and humid weather. One is hardly inspired to bake goodies when one is baking oneself everyday.
While I've made several savory dishes and some cinnamon rolls in the new oven with very good results, I hadn't yet attempted to make anything in the cake/muffin style. This evening, I gave a batch of pumpkin muffins a try and learned about some of the uneven heating patterns of the new oven. To be fair, all ovens seem to have this sort of problem though I'm guessing more expensive ones may lack them. My former oven was always hotter toward the front.
The new oven is a convection oven though so I had though it might be a bit better but the muffins tell no lies. If you look at the picture above, you can see it heats unevenly such that the left side bakes faster than the right and the air seems to blow harder from left to right such that the tops appear rather windswept. This doesn't make for very pretty presentation but it's not a big deal. The main thing I'll have to look out for is the fact that the right side seems to stay "raw" while the left cooks through. I'll have to turn the tray around at the mid-point of the cooking time to accommodate this weakness.
The finished muffins. They erupted over the sides because of the way they rose unevenly. Note how the ones in the back were swept both left and right and toward the center. They don't look so great but I'm sure they'll taste fine.
The odd thing is that all the muffins seem to have had their contents shift with the breeze in different directions. All I can imagine is that the convection blows in various directions and, depending on the position of the food on the tray, they are pushed one way or the other. One thing I did notice though was that regardless of position, the silicon bake-ware (the blue stuff) did a better job than the old aluminum ones. I had my husband pick up one "tin" of them while in the U.S. (they are much more expensive and harder to find in Japan) and now I wish I'd had him get two. Silicon "pans" are a bit flimsy and hard to handle when you fill them up (you have to put them on a flat surface that you can carry over to the oven) but they're better at conducting heat, cool off more quickly, easier to clean and don't require oiling (though it does help to oil them a little, they can be turned inside out to remove foods).