Slow Cooker French Onion Chicken Step-by-step instructions

Before you start

Before starting, pat the chicken thighs dry with paper towels and season them evenly with salt and pepper. Slice the onions into thin, even strips — a sharp knife makes this easier.

Measure out the broth, Worcestershire sauce, and other ingredients so everything is ready to go. Have a large skillet ready for searing and caramelizing, and a slow cooker plugged in and waiting. The prep takes about 15 minutes, and then the slow cooker does the work.

Instructions

Sear and Caramelize

1. 1Season and Sear the Chicken
   Pat the chicken thighs dry with paper towels. Season both sides with the kosher salt and black pepper. Heat the olive oil in a large skillet over medium-high heat. Place the chicken skin-side down and cook without moving until the skin is deep golden and crispy, about 5-6 minutes. Flip and cook another 4-5 minutes. Transfer the chicken to a plate; it will not be cooked through at this point.
   Look for The skin should be deeply browned and release easily from the pan.
   Tip Do not crowd the pan; sear in batches if needed to get a good crust.
2. 2Caramelize the Onions
   Reduce the heat to medium. Add the butter to the same skillet. Once melted, add the sliced onions. Cook, stirring occasionally, until the onions are soft and deeply golden, about 15-20 minutes. Scrape up any browned bits from the bottom of the pan as the onions release their moisture.
   Look for The onions should be reduced in volume and have a rich, jammy appearance.
   Tip A pinch of salt helps draw out moisture and speeds up caramelization.
3. 3Deglaze the Skillet
   Pour the beef broth into the skillet with the onions. Add the Worcestershire sauce, thyme sprigs, and bay leaf. Stir to combine, scraping up any browned bits from the bottom of the pan. Bring the mixture to a simmer, then remove from heat.
   Look for The liquid should be bubbling and the onions well coated.
   Tip Deglazing lifts the flavorful browned bits into the sauce.

The chicken should have a deep golden-brown crust on both sides, and the onions should be soft, glossy, and reduced to about half their original volume.

The skillet should have browned bits stuck to the bottom, which will flavor the sauce. The aroma will be sweet and savory.

Slow Cook

4. 4Assemble the Slow Cooker
   Pour the onion mixture into the slow cooker. Nestle the seared chicken thighs into the onions, skin-side up. Spoon some of the onions over the chicken. Cover and cook on low for 6-7 hours or on high for 3-4 hours, until the chicken is fork-tender and registers 165°F (74°C) in the thickest part.
   Look for The chicken should be very tender and the sauce fragrant.
   Safe temperature 165°F (74°C) internal temperature (poultry)
   Tip Cooking on low yields the most tender meat.
5. 5Thicken the Gravy
   When the chicken is done, carefully transfer it to a serving platter and tent loosely with foil. Remove the thyme sprigs and bay leaf. In a small bowl, whisk the cornstarch with the water to make a slurry. Stir the slurry into the slow cooker. Cover and cook on high for 15-20 minutes, until the gravy thickens.
   Look for The gravy should coat the back of a spoon.
   Tip Whisk the slurry well to avoid lumps.

After several hours, the chicken should be very tender and the onions completely soft and melting into the sauce. The liquid will have reduced slightly and the kitchen will smell richly of beef and thyme. The chicken should easily pull apart with a fork.

Thicken and Serve

6. 6Serve the Chicken
   Spoon the thickened onion gravy over the chicken thighs. Serve hot, with extra gravy on the side. The meat should pull apart easily with a fork.
   Look for The chicken should be glossy with gravy and easily shreddable.
   Tip Pair with crusty bread, mashed potatoes, or egg noodles to soak up the sauce.

The gravy should be thick enough to coat the back of a spoon, and the chicken should be glistening with sauce. The meat should be falling off the bone. A final taste for seasoning ensures the dish is perfectly balanced.

Common mistakes

One common mistake is skipping the searing step. Searing adds deep color and flavor that can't be achieved in the slow cooker alone. Another is overcrowding the skillet when searing, which steams the chicken instead of browning it.

Also, be patient with the onions — rushing them over high heat will burn them before they caramelize. Finally, don't add the cornstarch slurry at the beginning; it will break down and lose its thickening power during the long cook.

How to tell it’s done

The chicken is done when it is fork-tender and the internal temperature reaches 165°F (74°C) in the thickest part, measured with an instant-read thermometer. The meat should easily pull away from the bone.

The onions should be soft and deeply browned, and the sauce should be rich and flavorful. If the chicken is not yet tender, continue cooking in 30-minute increments until it is.

• Poultry: 165°F (74°C) in the thickest part