Season chicken with salt and pepper. Heat avocado oil in a large skillet over medium-high heat, add the chicken in a single layer and sear on each side for 3-4 minutes.
Transfer chicken to the slow cooker and cover with crushed tomatoes and tomato paste. Add remaining ingredients except for mushrooms and olives. Season with salt and pepper and lightly stir.
Cook on low for 7-8 hours or on high for 4 hours. 30 minutes before serving add olives and mushrooms to the slow cooker.
Remove bay leaves and transfer to large serving bowl. Garnish with grated parmesan and fresh parsley. Serve over whole wheat couscous, whole wheat pasta, quinoa, or spaghetti squash.
I recommend searing the chicken before adding it to the slow cooker, but if you are short on time it will still be delish without searing.
I have added olives and mushrooms at the beginning. I like the texture of the mushrooms better when they are added at the end. I really prefer to add the olives right before serving, but my husband prefers them to be added in the beginning, so I compromise and add them in with the mushrooms.
We recommend using organic ingredients whenever possible.