Sourdough baking is a craft that connects modern cooks to ancient traditions. Unlike bread made with commercial yeast, sourdough relies on a living culture of wild yeast and bacteria — a starter that must be fed regularly with flour and water to stay active. This feeding process is the most repetitive and time-sensitive part of sourdough, often requiring daily attention, frequent discarding of excess starter, and careful timing to ensure the culture is at its peak when it's time to bake. The Sourdough Sidekick, a new kitchen gadget developed by FirstBuild (the innovation hub behind GE Appliances' popular Opal ice maker) in partnership with King Arthur Baking Company, aims to automate this boring ritual.
What Is the Sourdough Sidekick?
The Sourdough Sidekick is a countertop appliance designed specifically to manage a sourdough starter. It consists of a glass crock where the starter lives, a motorized paddle that stirs the culture periodically, a detachable water tank, and a flour hopper on top. The machine measures out precise amounts of flour and water and dispenses them into the crock on a schedule that the user sets. It launched via crowdfunding in March 2025 and is now available directly from King Arthur for $179.99 — though only in the United States.
The core idea is simple: you add a small amount of your existing starter (15 grams, about a tablespoon) into the crock, fill the hopper and tank with your preferred flour and water, and tell the Sidekick when you plan to bake and how much starter you need. In Auto mode, the device calculates a dynamic feeding schedule that takes into account the ambient temperature, so that the starter reaches its peak activity exactly when you need it. It then stirs the mixture every two hours to incorporate the fresh ingredients and keep the culture aerated.
How It Performs: Auto Mode
In testing, Auto mode worked impressively with standard white bread flour. After setting a bake date a few days out, the Sidekick maintained the starter without any intervention. When the time came, the culture was vigorous, bubbly, and ready to use. In fact, the resulting bread rose well and had a pleasant tang, though it came out slightly overproofed — a sign that the Sidekick's controlled environment produced a more active starter than manual feeding typically yields.
However, Auto mode has several quirks. It requires exactly 15 grams of starter to begin with, so you must weigh that out each time. More frustratingly, the minimum amount of starter it will produce depends on the feeding duration. For a bake date a few days away, it can produce as little as 150 grams. But if you set the target four or more days out, it insists on making at least 400 grams — far more than most single-loaf recipes need. This results in significant discard, the excess starter that sourdough bakers usually compost or use in pancakes and crackers. The Sidekick also lacks a true maintenance mode: you must set a bake date within the next week. If you simply want to keep the starter alive without a specific baking plan, you must either set an arbitrary date (which forces more discard) or remove the crock and refrigerate it, partially defeating the purpose of automation.
Auto mode also struggles with non-standard flours. While it handled whole wheat and rye flours reasonably well after a short recalibration process (required to adjust for different flour densities), very coarse or dense flours, such as a robust rye from a small mill, created a starter too thick for the paddle to mix evenly. This left dry clumps and thin spots, compromising the starter's health. To fix that, you must leave Auto mode altogether.
Ratio and Custom Modes
For more control, the Sidekick offers Ratio mode and Custom mode. Ratio mode lets you choose from preset feeding ratios (typically 1:1:1 starter to flour to water, or variations) and set the seed amount and feeding frequency. However, it does not allow you to change the water-to-flour ratio independently — meaning you cannot make a thinner or thicker starter. That limitation drove the need for Custom mode.
Custom mode provides full flexibility: you set the seed amount, feeding frequency, and exact quantities of flour and water per feed. This allowed testing a looser, more hydrated starter that the Sidekick could mix easily. It also serves other purposes: FirstBuild provides instructions for using Custom mode to create a brand-new starter from scratch (which was achieved in four days) or to revive a neglected one. The downside is that Custom mode does not factor in ambient temperature, so you must monitor the starter's activity manually and adjust the schedule as needed.
Design and Usability Drawbacks
The Sourdough Sidekick is not a smart appliance in the usual sense. It has Wi-Fi and a companion app, but they are optional. The app sends notifications when the starter is ready or when discard needs to be removed, but the device's built-in screen does the same. The app also lets you view current settings but not change them, so there is little reason to use it.
Cleaning is a notable chore. FirstBuild recommends washing the glass crock, lid, and paddle after every feeding cycle to prevent buildup of old starter or mold. However, these parts are not dishwasher-safe, so they must be scrubbed by hand. The water tank and flour hopper can go in the dishwasher, but only occasionally. The device also makes noise: it stirs for 30 seconds every two hours, producing a distinct whirring sound that could be bothersome in a small kitchen or open-plan living space.
Who Should Buy the Sourdough Sidekick?
The Sidekick is clearly aimed at dedicated sourdough enthusiasts who bake multiple times a week. If you bake only one loaf a week or less, you will likely find yourself taking the starter in and out of refrigeration, manually feeding it between uses, and not fully benefiting from the automation. The $180 price tag and countertop footprint are hard to justify for occasional use. For the committed baker who makes two or more loaves weekly, however, the Sidekick can eliminate the most tedious aspect of sourdough: the constant feeding schedule and the guesswork of timing the starter's peak. It is essentially a specialized tool for a niche audience — much like a high-end espresso machine or a dedicated bread proofer.
The Sourdough Sidekick represents an interesting convergence of traditional food craft and modern automation. It does not replace the skill of kneading, shaping, or scoring bread, but it handles the one part many bakers find boring or stressful. Its limitations — such as the lack of a true maintenance mode, the noise, and the manual cleaning requirements — mean it is not a universal solution. But for those who fit its target profile, it could be a worthwhile addition to the kitchen. The device's origins with FirstBuild and King Arthur Baking Company ensure that it is built with input from both engineering and baking communities, and the ability to use a wide range of flours (with some workarounds) adds to its flexibility.
Ultimately, the Sourdough Sidekick does what it promises: it automates starter feeding. Whether that is enough to justify its cost and compromises depends entirely on how often you bake and how much you value that automation. The machine is available now from King Arthur Baking Company, and additional accessories and guidance are provided on the manufacturer's website. As with any single-purpose gadget, prospective buyers should weigh their baking habits carefully before committing to a device that may spend more time idle than active.
Source: The Verge News