Slow cookers are certainly popular—over 80 percent of American households has one. In such a crowded field, it’s tricky to sort out which is the best one to buy, especially when they all seem pretty much identical. I’ve spent the last year doing almost nothing but slow cook, writing a book called Adventures in Slow Cooking, which will be published in October by William Morrow.
My apartment looks like Hoarders: Slow Cooker Edition. I’ve learned that there are variables among slow cooker models that make a big difference in both your experience using the appliance and in the quality of the finished dish.
The slow cooker was invented by Irving Naxon in 1940. He called his gadget a Naxon Beanery, as it was inspired by the slow-simmered Jewish bean stew called cholent. In the ‘70s, he sold the rights to the Rival company, which rebranded it Crock-Pot. Some modern versions offer useful programmability and other bells and whistles, but the basic cooking mechanism hasn’t changed much since Naxon first came up with it. The pot (or “crock”) sits inside a casing that contains a wrap-around electrical heating element. The control panel on the outside of the casing offers warm, low and high heat settings.
The super-simple, closed design of the slow cooker is at the heart of its strengths and its weaknesses: It excels at any dish that requires low, moist heat. Obviously, that includes anything braised or steamed, but it can also gently poach delicate fish, or be deployed as a water bath for making foolproof custards and cheesecakes. It uses less energy than the stove or oven (most require about the same wattage as a lightbulb or two), and you can leave it on all day without worrying you’re going to burn your house down.
However, a slow cooker can over-cook your food. Modern models run considerably hotter than the originals from the ‘70s, because of concerns about food safety. (The rule of thumb is that cooked food should not be held between 40˚ and 140˚ for more than four hours.) And there’s no standard temperature for the low, hot and warm settings. They can vary by as much as 30 degrees from model to model. That’s why it’s so important to choose the right machine: If you are using the slow cooker for all-day cooking, you want one that runs as low and slow as possible.
So, out of the hundreds of slow cookers on the market, I tested some of the most popular to find out which one performs the best. I started with these three guiding principles:
1. The most useful size for a slow cooker is a five- to seven-quart oval. A six-quart oval slow cooker can make a recipe that serves four, but it will also accommodate large roasts or whole chickens. A two-quart souffle dish or a loaf pan can fit inside, for making bread pudding or cheesecake. There’s nothing you can do with a four-quart slow cooker that you can’t do with a six-quart, but the reverse is not true. There’s no question that if you’re going to buy one slow cooker, it should be this size and shape.
2. Programmability is a must-have feature. A programmable slow cooker allows you to set cook time and heat level (say, 4 hours on low) and after the time has elapsed, the cooker will automatically switch to warm, decreasing the temperature. The warm setting shouldn’t be abused—you can’t just leave chicken on warm for four hours and expect it to still be juicy. But it’s a lifesaver for a gap of a few hours between when a recipe is done and when you get home. Dishes like marinara sauce and polenta can sit on warm for hours without suffering. The older and simpler models just run on whatever heat level you’ve set it to until you get home and switch it off, making overcooking much more likely.
3. It is nice, but not necessary, to have the ability to sear or brown in the slow cooker insert. Many recipes call for sautéing aromatics and/or browning meat before slow cooking. If you can do this in the slow cooker insert, you don’t have to use a separate skillet on the stovetop.
Starting with those parameters, I tested seven popular slow cookers from six different brands, four with browning ability, to see which offered the best user experience and low, even cooking.