Edible Seasonals: Nasturtiums
Vegetable, herb, fruit, flower
By Ellen Jackson
Photo by Joshua McCullough
“Use everything” is the mantra of any well-run professional kitchen, where food cost is tied closely to success. So I wasn’t surprised when many of the chefs contributing to the book I spent the last year writing, The Chefs Collaborative Cookbook, sent me recipes for Rainbow Chard Stem Gratin (bubbly, cheesy and breadcrumb topped), Broccoli Hushpuppies (made with the stems and cheddar cheese, they beg to be dipped in apple butter or garlicky ranch dressing) and Pappa al Pomodoro (the Tuscan porridge-like soup made from overripe tomatoes and yesterday’s bread). Still, I wasn’t expecting Nasturtium Soup with Braised Pistachios (find recipe here).
Tropaeolum majus are known by their common name, nasturtium, because they produce oil similar to nasturtium officinale, or watercress, a close family member. Classified at various times in history as vegetable, herb, fruit and flower, nasturtiums are all those things. Traditionally they have played a dominant role in the garden, where they brighten borders and thrive in poor conditions, but I think nasturtiums also belong in the kitchen. The flowers, which are edible, make an arresting addition to salads and main courses. The pale green flower buds, which look like tiny zombie brains, can be picked at summer’s end and pickled like capers. And then there are the leaves.
Grassy green and shaped like Capuchin monks’ robe hoods, leaves of the flowering plant are packed with vitamin C and have a pungent, peppery flavor that is equally at home on an egg salad sandwich or in place of arugula on a pizza. Tender young foliage might become salad, pesto or a bright sauce to spoon over grilled fish. Larger, more mature leaves stand in nicely for grape leaves, holding up well to stuffing, rolling and heat.
Plant nasturtiums at the base of your fruit trees, or in and around your kitchen garden. Once you’ve eaten your fill, allow the aphids and slugs that adore them to feast on their leaves; in doing so, they’ll be distracted from the more precious crops above and around them. It’s all about making your ingredients work for you.
Creativity and thrift are tenets of the food revolution sweeping the country. And not just in professional kitchens. Home cooks everywhere are pickling watermelon rind, buying whole animals directly from their producers and putting up what looks like too many quarts of tomatoes, but is never enough. What’s next? Nasturtium Soup, that’s what.
Find recipes for Nasturtium Soup and more in The Chefs Collaborative Cookbook, a celebration of 20 years of work by the national Chefs Collaborative organization, which brings together 6,000 chefs, farmers, fishers, educators and other food professionals to promote a clean, resilient food supply.
Quick & Easy
Combine tender young nasturtium leaves and petals with mild greens, spinach, mâche or miners lettuce, fruity olive oil and lemon juice. Or lightly coat the leaves with buttermilk dressing spiked with toasted fennel seeds, and toss with roasted beets and thin slices of fennel and tart apples, or wedges of creamy avocado and orange or grapefruit sections. Use the leaves in the same places that watercress would be welcome: on egg and chicken salad sandwiches, chopped and folded into crab or shrimp salad, or piled on slices of bread thickly spread with sweet butter and sprinkled with coarse salt.
Toward the end of summer, when the blossoms have faded and dropped, gather the soft, still-green seeds of the nasturtium plant to make capers. Soak the seeds in cold, salty water before covering them with white wine vinegar infused with fresh herbs and spices. Bay leaves, garlic, celery seeds, peppercorns, whole cloves and lemon zest all make good additions. After 3 to 4 weeks, the capers are ready to be used. Put them in a warm potato salad, sauce verte or a pan sauce for fish made with brown butter, lemon juice and parsley.
Oh, how our definition of pesto has expanded! These days, we make it with marjoram, nettles, asparagus and sorrel. When substituting nasturtiums for basil, stick to the usual formula and ratios as the leaves are naturally assertive and able to hold their own next to pesto’s other strong flavors. Try toasted walnuts instead of pine nuts. Stir the pesto into vichyssoise, spread it on pizza dough before topping with shaved asparagus and Parmesan and baking, or spoon it over roasted cauliflower. Thinned slightly, it becomes a delicious sauce for lamb chops, poached halibut or grilled salmon.
Grape leaves can be difficult to work with when making dolmas; large, mature nasturtium leaves are supple and less likely to tear, and stand up to steaming. Stuff them with a traditional ground lamb and rice filling, or experiment with grains like quinoa or farro and roasted vegetables. Blossoms can be filled with herbed goat cheese, cream cheese or mascarpone.
Ellen Jackson is a Portland-based writer, cookbook author and food stylist.