01 -
Sprinkle both sides of the chicken thighs with Italian seasoning, salt, and pepper.
02 -
In a large skillet over medium-high heat, melt butter with olive oil.
03 -
Add the diced onion and minced garlic to the skillet and sauté for about 2 minutes.
04 -
Move the onions and garlic to the side of the skillet and add the seasoned chicken thighs. Sauté for 2-3 minutes on each side until nicely browned.
05 -
Transfer the contents of the skillet (chicken, onions, and garlic) to the slow cooker. Add chicken broth to the slow cooker.
06 -
Cover the slow cooker and cook on low for 5-7 hours or on high for 3-4 hours.
07 -
Remove the cooked chicken thighs from the slow cooker and cover to keep warm.
08 -
Add heavy cream, grainy mustard, and lemon juice to the slow cooker. Whisk until combined.
09 -
To thicken the sauce, transfer it to a small saucepan and whisk in 1 tablespoon of cornstarch. Bring the sauce to a boil and cook for 2-3 minutes until thickened to your desired consistency. Adjust seasoning with additional salt and pepper, if needed.
10 -
Pour the sauce over the chicken thighs and serve.