1½ c. ricotta
1 c. Italian cheese blend, plus more for topping
1 large egg
kosher salt
Freshly ground black pepper
½ c. (1 stick) unsalted butter
1 c. heavy cream
½ c. freshly grated Parmesan
Fresh basil, torn, for serving
Preheat oven to 350°. In a large pot of salted boiling water, cook pasta shells until al dente. Drain, then return to pot and let cool. Meanwhile, in a large bowl, stir together ricotta, Italian cheese, and egg, and season with salt and pepper. Stuff mixture into shells. In a saucepan or skillet over medium-low heat, melt butter. Add cream and bring to a simmer, then stir in Parmesan and season with pepper. Pour ⅔ of the sauce into an oven-proof skillet or baking dish, then arrange stuffed shells on top of sauce. Spoon remaining sauce over shells and sprinkle with more cheese. Bake until cheese is melted and bubbly, 18 to 20 minutes. Garnish with basil and serve.