Coat the chicken with flour and shake off the excess. Over medium heat, in a saucepan with extra virgin olive oil, brown the chicken then season with salt and pepper. Do not overcrowd. Cook in batches if needed. Pour 1 cup chicken broth in the saucepan and cook until the sauce thickens.: The moment you put the floured pieces into a warm pan you'll hear a soft sizzle, which is the start of flavorful browning. As the surface of each chicken piece caramelizes, it creates fond, those brown crumbs that stick to the pan and hold concentrated taste. That fond is essential because when you later add liquid, it dissolves and enriches the sauce, giving the stew a deeper savor. Use a light, even dusting of flour so the coating is thin, otherwise you risk a pasty texture. A typical mistake here is overcrowding the pan which cools the surface and leads to steaming instead of searing. Work in batches if needed, and keep the pan hot enough that each piece browns quickly but does not burn. Visually, you want golden edges rather than gray or charred spots.
Transfer the contents of the saucepan to the slow cooker. Add a little bit more extra virgin olive oil in the saucepan then sauté the onions over low - medium heat for about 5 minutes. Transfer the onions to the slow cooker. Add the squash, remaining chicken broth, and sage in the slow cooker. Set on low for 4 hours.: Once the chicken hits the hot oil, listen for consistent sizzling and watch the edges turn to a warm golden color. Browning concentrates the meat's flavor and creates texture that holds up during slow cooking. Sprinkle the measured salt and pepper as the pieces turn so seasoning adheres and penetrates. If the pan gets too crowded, the temperature drops and the meat will release more moisture, which prevents a proper sear. Use moderate heat so the outside browns without overcooking the interior. Smell is a great indicator here; a toasty, nutty aroma means the browning is progressing well.
Do not overcrowd: When pieces are too close together you will see steam and little to no browning, and the surface will remain pale instead of developing a bronzed crust. Proper spacing ensures air and heat circulate, producing even color and texture. If you must cook in batches, keep finished pieces on a warm plate, uncovered briefly so steam escapes and the crust stays crisp. A common slip is stacking the cooked chicken which traps steam and ruins the sear you worked for, so spread them out instead.
Cook in batches if needed: Handling the chicken in organized batches means each piece receives proper contact with the pan. As each batch finishes, the pan may develop sticky browned bits, which is expected and desirable. Save those bits because they become the base for a richer broth after deglazing. Resist the urge to rush this step; the slow cooker can tenderize, but it cannot create the concentrated caramelized flavor that searing produces. Overcrowding to save time leads to a flatter final taste.
Pour 1 cup chicken broth in the saucepan and cook until the sauce thickens: When you add that first cup of chicken broth to the hot pan, you'll hear a hiss as it hits the residual oil and heated fond. Scrape the bottom with a wooden spoon so the fond dissolves into the liquid, releasing concentrated flavor. Cook until the liquid reduces slightly and coats the spoon, which signals a richer, slightly thickened sauce. This deglazing step is crucial because it pulls all the caramelized flavor into the stew. Avoid adding too much liquid here or you dilute those concentrated flavors; reduce patiently until you see a glossy coating.
Transfer the contents of the saucepan to the slow cooker: As you move the pan contents, notice the scent of the concentrated broth that now clings to the chicken . That aroma is a good sign the foundational flavors are in place. Transfer everything, including any little browned bits and reduced sauce, because they will continue to infuse the stew during the long, gentle cook. A frequent oversight is leaving flavorful pan residue behind; use a spatula and a small splash of broth to scrape every last bit into the cooker.
Add a little bit more extra virgin olive oil in the saucepan then sauté the onions over low medium heat for about 5 minutes: The moment the chopped onion hits the warmed oil, its edges should start to become translucent and soft, and a faint sweet fragrance will appear. Sautéing at low medium heat encourages the onion to sweeten without browning too quickly, which maintains a delicate flavor that complements the squash . Stir gently and watch for translucence rather than deep color. A common error is cranking the heat in pursuit of speed, which causes the onion to color too much and develop a bitter edge that can unbalance the finished stew.
Transfer the onions to the slow cooker: When the onion is soft and slightly sweet smelling, move it to join the chicken in the cooker so their flavors mix during the long simmer. The softened onion will melt further into the broth, rounding the overall profile and providing a gentle sweetness that contrasts the herb notes. Make sure you transfer any fond or oil left in the pan to avoid losing that flavor. Leaving those bits behind is probably the most common missed opportunity at this point.
Add the squash remaining chicken broth and sage in the slow cooker: Add the diced squash , the remaining measured chicken broth , and the fresh sage so they can meld slowly. As the cooker warms, the squash will soften and release natural sugars, gently thickening the broth while the sage infuses an herby warmth. Stir lightly to distribute ingredients evenly, ensuring each spoonful will have a mix of meat, veg, and broth. Avoid over stirring which can break down the squash too early and make the stew excessively mushy.
Set on low for 4 hours: Setting the slow cooker on low lets flavors develop slowly and keeps textures tender without falling apart. Over those hours the aroma will become rounded and cohesive, the chicken will finish cooking through, and the squash will reach a pleasing tenderness that still holds shape. A punishing mistake is using high heat to speed things up, which often yields uneven results, tougher meat, or overcooked squash. Low, patient heat is what produces that homey, melded flavor.
