To prepare the sauce, whisk all of the ingredients together and set aside.
Lightly spray or brush the interior of your slow cooker with oil.
Add the chicken breast, carrots, and onion. Season with salt and pepper and add 1 tsp of avocado oil. Toss to coat.
Pour the sauce over the chicken and vegetables and cover the slow cooker for 3.5-4 hours on low.
Remove the lid and add the broccoli florets. Whisk the arrowroot starch with about 1 tbsp of water (or chicken broth) and add it to the slow cooker. Lightly stir and cover for 30 minutes to allow the broccoli to soften and the sauce to thicken.
Remove the lid and gently stir to coat the chicken and vegetables in the sauce, adding more arrowroot and water mixture if a thicker sauce is desired. Use a thermometer to ensure the internal temperature of the chicken is 165 F.
Serve the chicken and broccoli with a side or rice or cauliflower rice and top with green onion!
Notes
I use frozen broccoli because frozen broccoli is preblanched and has a better texture! I find it best to let it sit out for about 20 minutes before adding it to the slow cooker. You can also use fresh broccoli but it may need a touch more cook time.