Combine cream cheese and milk in a blender. Blend until smooth.
Add cauliflower, cream cheese mixture, butter, salt, and pepper to a slow cooker. Cook on low 3 hours. Add pepper jack cheese. Cook on high 30 min.
To Freeze
Blend cream cheese and milk in a blender. Add cream cheese mixture, cauliflower, butter, salt, and pepper to a freezer bag. Add pepper jack cheese to a separate freezer bag. Add both bags to a third freezer bag. Freeze.
To Cook After Freezing
Add contents of first bag to a slow cooker. Cook on low 3 hours. Stir in contents of 2nd bag. Cook on high 30 minutes.