We write an awful lot about the KettlePizza—the after-market insert that converts your Weber grill into a pizza oven—here on Slice, and with good reason. After a few initial hiccups getting the thing to work, we eventually managed to get it to produce some of the finest pies we've cooked at home with only a couple of very minor hacks.
Since then, we've also met with Al Contarino, the maker of the KettlePizza and worked with him on improving its functionality straight out of the box. To his great credit, he has been extremely open to modifying the design and taking our feedback into account.
His past innovations include a tombstone-shaped stone to bake the pies on for easier launch and retrieval and a new rack for the stone, allowing for quick re-loading of coals and wood (without having to disassemble and reconstruct an 800°F grill in the middle of a pizza party).
The newest model of the KettlePizza is yet another step in the right direction.
I'd mentioned in the past that one of the KettlePizza's biggest drawbacks is the size of the airspace above the pizzas as they cook. Because of the insert's tall profile, along with the high domed lid of the Weber kettle, getting the top of a pizza to cook efficiently has been a struggle. It's for this reason that I found covering the top opening of the KettlePizza with an aluminum foil-coated grate can vastly improve the quality of your finished pies.
The new KettlePizza insert is a good 20% shorter and features a thermometer that's been shifted to the side of the launching mouth so that it doesn't get in the way when you're moving pies in and out.
The important questions: How does this improvement affect the final product? And will it preclude the necessity of the foil cover?
I fired it up a couple weeks ago to find out.
Test 1: KettlePizza Alone
First off, I fired it up straight out of the box, no hackery whatsoever. I was impressed to see that with a single chimney of coal and no assistance from foil or extra stones, I was able to get the base temp up to above 500°F (the photo is bit misleading; Most of the rest of the stone was at around 500°F—there happened to be a hot spot when I snapped the shot) with a dome temp in the 700 to 800°F range. With the older model, this required over 20 pounds of coal to achieve.
I launched a pepperoni pie into the mouths of the beast and watched as it cooked. It took around 5 minutes total and came out looking like this:
Not bad. A little pale, but nice and puffy with a few darker spots. The underbelly was even better:
Near picture perfect.
But that demonstrates again the issue that remains with the out-of-the-box KettlePizza: the tops never cook enough.
I'm not saying the pizza was bad by any means. A few years ago, I would have been pleased as punch to pull a pie like this out of my oven. But now that I've seen the power of the slightly-hacked KettlePizza, other cooking methods pale in comparison.
Test 2: KettlePizza with Aluminum Foil
The difference a couple square feet of foil can make! By covering the top of the kettle pizza with a foil-wrapped grill rack, you can effectively cut the air space above the pizza down to about half its original height. The flames lick up and over the pie, and air-flow is increased, delivering fresh hot air to your pie constantly. The pizza cooks in just 3 to 4 minutes, and comes out with a burnished brown crust on top and gorgeous leopard spots underneath.
Test 3: KettlePizza with Foil and Baking Steel
Finally, I cooked one using my recent go-to method: combining the heating power of the KettlePizza and its stone underneath while using the heat-retaining and re-emitting properties of the Baking Steel above, along with an aluminum foil roof to manage airflow.
Gape into the mouth of the oven and you can see how blazing hot it gets. The floor temperature hovers at around 700 to 750°F, but the roof temperature buries the needle on both my IR thermometer and the dial thermometer on the KettlePizza. I'd guess it's in the 900 to 1000°F range.
As you can see, it's still a superior finished product to either the KettlePizza-only pies or the KettlePizza-plus-aluminum foil pies.
Moral of the story? The KettlePizza and Baking Steel combo remains the very best way I know of to cook pizza at home without building yourself a wood-fired oven, and now's a better time than ever before to pick one up. But if you've already got the original Kettle Pizza, there's no need to upgrade just yet, the performance increases exist, but they're still just tweaks.
About the author: J. Kenji Lopez-Alt is the Chief Creative Officer of Serious Eats where he likes to explore the science of home cooking in his weekly column The Food Lab. You can follow him at @thefoodlab on Twitter, or at The Food Lab on Facebook.