Heat the cream in a large pan over medium-high heat until small bubbles begin to form in the middle and on the sides, Add the Gorgonzola and cook, stirring, until it’s completely melted. Reduce the heat to medium and whisk in the flour. Cook, stirring, until the sauce is slightly thickened, about 3 minutes more. Turn off the heat and cover to keep warm.Cook the Gnocchi and Toss with the Sauce and finish with parsley and lemon.
Put the unpeeled potatoes in a large pot. Fill the pot with enough cold water to cover and bring to a simmer over medium-high heat. Reduce the heat to medium, partially cover the pot, and simmer the potatoes until they are completely tender and easily pierced with a skewer, 30 to 35 minutes. Drain the potatoes, let them cool just enough that you can handle them, and then peel them. Cut them in half crosswise and pass them through a ricer into a large bowl. Let cool until almost at room temperature, at least 20 minutes. Lightly flour a work surface. In a small bowl, mix the flour with the salt. Add the egg to the potatoes and then add the flour mixture. Mix with your hands until the flour is moistened and the dough starts to clump together; the dough will still be a bit crumbly at this point. Gather the dough together and press it against the bottom of the bowl until you have a uniform mass. Transfer it to the floured surface and roll into a 1cm thick tube, cut into little 1.5 cm pieces and blanch in salted boiling water. When they rise to the top they are ready, fish them out and into the cheese sauce.