Start by greasing the inside of your slow cooker with nonstick spray or a drizzle of olive oil.

Arrange the boneless, skinless chicken breasts or thighs in a single layer at the bottom of the slow cooker.

In a separate bowl, whisk together honey, Dijon mustard, yellow mustard, minced garlic, olive oil, chicken broth, salt, and black pepper until smooth.

Gently pour the honey mustard mixture over the chicken, ensuring all pieces are evenly coated.

Cover the slow cooker and set it to LOW for 6-7 hours or HIGH for 3-4 hours.

If you prefer a thicker sauce, remove the chicken after cooking and whisk cornstarch with cold water until dissolved, then stir into the sauce in the slow cooker.

Once the sauce has thickened, return the chicken to the slow cooker, tossing gently to coat.

Before serving, sprinkle fresh parsley over the chicken.