While cleaning out the freezer in The Perfect Pantry recently, I discovered some cooked pasta, half a bag of frozen peas, and a long-forgotten container of pesto made from the last of last summer's parsley (gosh, that's a lot of P in one sentence, isn't it?). In fact, my pantry offered up every ingredient for this dish of pasta with peas and parsley-walnut pesto. If you don't have homemade pesto tucked away in your freezer, use store-bought basil pesto, and you will be very happy. And if you prefer whole wheat or gluten-free pasta, use what you love. Be sure to use good white wine and real Parmigiano-Reggiano cheese; when a recipe has just a few ingredients, your happiness depends on using the very best you can afford.