Bring a large pot of lightly salted water to a rolling boil over high heat; stir in the frozen ravioli and return to a boil. Cook uncovered, stirring occasionally, until the ravioli float to the top and the filling is hot, 6 to 8 minutes. Drain.
Meanwhile, bring the half-and-half to a simmer in a saucepan over medium heat. Whisk in the Gouda cheese until melted; season with parsley and white pepper. Pour the sauce over the cooked ravioli to serve.
