MELT 1 Tbsp. of the butter in large deep nonstick skillet on medium-high heat. Add mushrooms; cook and stir 7 to 8 min. or until tender and golden brown. Remove from skillet.
ADD remaining 1 Tbsp. butter and onions to skillet; cook and stir on medium heat 7 to 8 min. or until onions are tender and golden brown. Stir in rice until well blended. Add broth and pepper; stir. Bring to boil. Reduce heat to medium-low; cover. Simmer 5 min. or until rice is tender.
STIR in shrimp and parsley; cover and let stand 10 min. or until shrimp are heated through. Add mushrooms and cheese; stir.