Step 1

Add the broccoli, onion, garlic, chicken, broth, cream, ground mustard, salt, pepper, and red pepper flakes to a 6 quart slow cooker.

Step 2

Cover and cook on low for 4 hours or until the broccoli is very tender.

Step 3

Use an immersion blender to blend the soup to a smooth consistency. Alternately, carefully transfer the soup to your blender in batches and blend. Be careful while blending hot soup and be sure to vent the steam when blending hot soup.

Step 4

Add the cheese to the hot soup and stir well until melted and creamy.

Step 5

Serve immediately with additional grated cheese and crumbled bacon, if desired.