Place peppers in slow cooker sprayed with cooking spray; top with potatoes.
Sprinkle paprika over chicken.
Place half the thighs in slow cooker; cover with soup and remaining thighs. Cover with lid.
Cook on LOW 6 to 8 hours (or on HIGH 3 to 4 hours).
Use slotted spoon to transfer chicken and vegetables to platter; cover to keep warm. Set slow cooker on HIGH heat.
Add VELVEETA and Worcestershire sauce to reserved liquid in slow cooker; stir. Cover with lid; cook 5 min. Stir until VELVEETA is completely melted and sauce is well blended. Spoon over chicken and vegetables; top with parsley.