King Arthur Baking Sourdough Sidekick Review: Rising to the Occasion

TriangleUp Buy Now Multiple Buying Options Available $180 at Shop $180 at King Arthur Baking Save Story Save this story Save Story Save this story Rating: 8 /10 Open rating explainer Information WIRED A hands-off way to maintain your sourdough starter so it’s ready when you need it. Ensures no missed or forgotten feedings. Small enough to fit unobtrusively on most countertops. All variables are customizable. TIRED No temperature control. Mixing cycle is loud and can be startling. Calibration is fiddly, especially if you frequently switch between flour types. Like many people, I enjoy baking my own bread—especially this time of year. I baked sourdough on and off for nearly a decade, even having a recipe tested for a James Beard-winning bread cookbook, but I’m not proud to admit it’s been over a year since I baked a proper sourdough loaf. As a full-time working parent, maintaining a sourdough starter sometimes feels like bringing home another pet. (You know, the kind your child swears they will care for before abandoning all tasks after three days.) You can certainly keep your starter in the fridge for around a week between bakes, but reviving it may take a day or two of feedings, and let’s be real, Will you remember to do this every week? Even the pet snake my son begged for only needs feeding every other week. It is for people like me that King Arthur Baking Company and FirstBuild, GE Appliances’ product development lab, created the Sourdough Sidekick, a gizmo that automatically feeds and maintains a sourdough starter for you. We wrote about the Sourdough Sidekick when it was first announced in 2025 , and now, after trying it for three weeks, I can say that my sourdough-baking dry spell has finally come to an end, perhaps even permanently. A Rocky Starter Sourdough Sidekick, pictured here with the optional Crock Grip Band ($15) Photograph: Kat Merck The Sidekick is a Mr. Coffee-sized appliance with a built-in water reservoir, flour hopper, and glass crock with a stirring-paddle lid. I deal with an awful lot of apps in my job, and the Sidekick uses GE’s generic SmartHQ for GE appliances, which isn’t specific to this device and seemed optional. I admit I couldn’t be bothered with an unnecessary app, so I didn’t download it. Instead, I followed the directions in the included Quick Start Guide booklet, which indicated that I simply needed to fill the water reservoir and flour hopper, set the current day and time (and the day and time I wanted the starter to be ready—you can choose up to seven days ahead; I chose seven), add a little bit of existing starter, and press “Auto Mode.” Almost immediately, a torrent of flour released from the hopper and began mixing into my seed starter with the stirring paddle. (King Arthur recommends keeping a portion of your starter in the fridge in case things go wrong, and I second this suggestion.) Oddly, no water was dispensed in this process, so post-mixing, my starter was now in the form of an under-hydrated ball. Over the next few days, it became a larger, drier ball until I finally decided to remove the crock to add a couple of tablespoons of water; as I did, I noticed the reservoir was still at its maximum fill line. I decided I should probably download the app, where I noticed the Sidekick indicated it needed a firmware update. After the update, the Sidekick began dispensing water during mixing, but I realized I really should have followed the instructions in the main instruction booklet, which calls for using a scale to properly calibrate the amounts of water and flour the machine dispenses. Theoretically, you should only have to do this once, which is good because it’s an irritatingly lengthy and fiddly process. However, my next attempt (remember when I mentioned saving some starter in the fridge?) went much better, properly dispensing 30 grams each of water and flour each day and initiating a stirring cycle every two hours. It starts with a loud beep, then the paddle begins a loud mechanical whir, and for the first few days this can be quite startling, especially if you’re in the same room when it happens. Photograph: Kat Merck You can bypass the every-two-hours stirring cycle via the onboard controls, but since the stirring’s purpose is to knock down the starter’s volume and reincorporate any unconsumed flour, I kept it on. (For what it’s worth, I did think the paddle, an update from the Sidekick’s first design, did a pretty good job of incorporating all of the flour and water each time it mixed.) Note that, in part due to the regular mixing and the lack of discard (Auto Mode will prompt you to discard after a week, while Ratio and Custom modes, detailed below, will have discard reminders), your finished starter in the Sidekick may not look as traditionally puffy or bubbly as you may be used to. You can disable stirring, or you can go on scent—it should smell tangy and indisputably fermented. As the many online Sidekick adherents often say, “Trust the process.” Some online users recommended adding a few teaspoons of more nutritionally dense rye flour to the (presumably all-purpose) flour in the hopper, which is supposed to supercharge the starter’s growth, but I admit I didn’t notice much of a difference in appearance, smell, or performance between an all-purpose starter and a rye-boosted starter. Boules made with end-of-week starter maintained via the Sourdough Sidekick Photograph: Kat Merck Loaf and Learn Other than enabling firmware updates, the app does little beyond displaying the machine’s current settings and sending a push notification when the starter is finished. You can’t adjust settings or control the machine from it, but the most recent firmware update supports power-loss recovery up to 12 hours , which I tested and found successful after my husband tripped a breaker one day. The display shows the ambient temperature, but unlike other starter-babysitting gadgets like the Goldie or Brod & Taylor’s Sourdough Home , the Sourdough Sidekick has no way to adjust the starter’s temperature, which could be an issue if your house or kitchen runs cold. It does, however, offer “ temperature-aware ” feedings in Auto Mode, adjusting amounts based on detected room temperature. Screenshot: Kat Merck In addition to Auto Mode, there’s Ratio Mode (where you can indicate starter-flour-water feedings by ratio—1:1:1, 1:1:2, et al.) and Custom Mode, which is what I ended up using the most, as I like to switch between flour types for different kinds of bread—you can dictate the exact flour and water quantities, as well as timing of the feeding (once a day, or even twice a day). In a typical week, the crock was about two-thirds full by the end, with more than 400 grams of starter—enough for two boules and a sandwich loaf with some seed left over for the next batch—ready to use right out of the crock. The resulting bread turned out no differently than it had with traditionally maintained starter. If you’re unable to bake at that time, you can just discard most of the starter, leaving some “seed” behind for the next batch, or keep it in the refrigerator for a few days before reviving it the traditional way. (The crock comes with a metal lid for this purpose.) If you’re only baking one loaf, you’ll have excess, but you can use the discard in recipes or give it away. Just note that if you intend to make a starter with a different flour, like whole wheat or full rye, you will need to calibrate the machine again as you did at the beginning. All removable components are top-rack dishwasher safe. The Sourdough Sidekick is one of the most compelling kitchen-tech gifts I’ve ever seen for someone who bakes a lot or is interested in sourdough baking but intimidated by the process of keeping a starter. (The Sidekick also includes directions for making your own starter right in the machine.) Is it a necessary device? Of course not—especially since it costs about $175 more than a