Right about now, I get to craving the aromatic bliss of basil. But it’s tough to find in winter, and tends to be somewhat bland–and expensive–if you do. My seasonal secret? I use arugula, which is abundant right now both in my garden and on market shelves. The fresher the arugula, the more pungent the whole experience will be; for even more punch, pound the pesto in a mortar and pestle. This recipe makes a double batch of arugula pesto. The extra will keep in the fridge for up to 3 days, or you can freeze it for up to 6 months. This garlicky, spicy pesto is terrific with roast chicken, as a sandwich spread or dolloped on crostini with goat cheese.