"Stinging nettle is one of the most nutritious foods native to North America. I absolutely love it in soup, in place of basil in pesto, or simply steamed with butter. This is one of my favorite ways of preparing nettles, though. With cream and cheese, how can one go wrong? Serve as a side dish with fried oysters or in a small bowl on its own. A dollop of creme fraiche or ricotta cheese on top would be classy."
Bring a large pot of salted water to a boil. Add nettles; cook until wilted, about 4 minutes. Drain, reserving cooking water.
Transfer drained nettles to a blender; blend until smooth.
Melt butter in a large skillet over medium-low heat. Add shallots; cook and stir until very soft, about 10 minutes. Stir in heavy cream, salt, and pepper. Simmer until cream coats the back of a spoon, about 2 minutes. Stir in Parmesan cheese and blended nettles until well-combined.