In a wok or large non-stick skillet on a medium to high setting, add the butter, onions, Rotel, mushrooms, and garlic and stir. Cook 15 to 20 minutes or until vegetables are tender and water has evaporated. Add the shrimp and sprinkle Mr. Pete’s Cajun Seasoning on top. Once again, stir and simmer for another 10 minutes or until the water cooks out. Serve this dish over rice or pasta and enjoy!