In the bottom of the crockpot, place the chicken breasts and season with garlic powder, onion powder, salt, and black pepper.
Pour the chicken broth and heavy cream over the chicken. Drizzle with olive oil and add the Dijon mustard.
Cover and cook on low for 6-7 hours or on high for 3-4 hours, until the chicken is cooked through and tender.
About 30 minutes before serving, add the broccoli florets to the crockpot. Stir gently to combine.
Once the chicken is cooked, shred it using two forks directly in the crockpot.
Stir in the shredded cheddar cheese and grated Parmesan cheese until melted and creamy.
Serve warm, garnished with additional cheese if desired.