If using refrigerated or frozen cooked lobster, make sure it is fully thawed and drain away any excess liquid. Cut the meat into bite-size chunks and set aside.
In a small bowl, whisk together the heavy cream and egg yolks until completely smooth. Keep the mixture ready while you begin the sauce.
Melt the butter in a medium saucepan over low heat. Once melted, slowly add the cream and egg mixture while whisking constantly.
Stir in the sherry and continue cooking over low heat for about 5–8 minutes, stirring frequently, until the sauce thickens enough to coat the back of a spoon. Do not allow it to boil, as excessive heat can cause the egg mixture to curdle.
Remove the saucepan from the heat and stir in the salt, paprika, cayenne, nutmeg, and lemon juice. Taste and adjust the seasoning as needed.
Gently fold the cooked lobster chunks into the warm sauce. Return the pan to very low heat and warm for about 3–5 minutes, stirring gently, just until the lobster is heated through. Avoid boiling.
Spoon the creamy Lobster Newburg over buttered toast, puff pastry shells, or warm pasta. Garnish with fresh parsley and serve while hot.
