Less expensive than fresh truffles (the most prized varieties of which can cost up to $1,400 per pound), a high-quality truffle oil adds an earthy, complex taste to pasta dishes such as the gnocchi with peas and chanterelles. It's also added to whipped preparations like deviled eggs and mashed potatoes to add unexpected depth of flavor. Truffle oils range in color from clear yellow to cloudy green; some include a sliver of whole truffle in the bottle. All-natural truffle oil is usually made by infusing olive oil or grapeseed oil with pieces of truffle, though many producers these days augment their product with a chemical compound that mimics the truffle's taste and aroma, making for a more potent but less refined (and sometimes acrid) taste. We prefer the purer character of all-natural oils like Truffieres de Rabasse Black Truffle Olive Oil, from France ($36), and Oregon White Truffle Oil ($30), which contains the essence of Oregon truffles (it's the only truffle oil currently sold in this country containing domestically grown truffles). Truffle oil should be stored in a cool, dark place.