After the seemingly endless winter, it's been a quick transition. Put away parka, unpack tank tops. Are you brave enough to try on some swimsuits yet?

Whether or not you are concerned about the state of your waistline, now is a good time to eat more vegetables. The sunshine and warmth makes us a little more energetic, and a little less interested in rich food. Go with it, and follow the seasons with a big vegetable soup, topped with a dollop of garlicky pistou.

Eating more vegetables isn't simply a good way to drop a pound. It's also a good way to savor the fresh, flavorful plants that will keep you humming along. A bowl of vegetable soup is filled with health-supporting vitamins, minerals, antioxidants and fiber. This one has white beans, to make it into a filling meal on its own. A classic pistou will add big flavor, and by adding sweet peas to the mix, even more vegetables.

Pistou is the French version of pesto, and where it started first depends on who you ask. In Nice, France, pistou is made by pounding basil, garlic, olive oil and an aged cheese.

In Genoa, Italy, pesto is made in a similar fashion, with pine nuts added. For our light and springy version, I put in sweet peas to replace the nuts and cheeses. Sweet peas are an essential flavor of spring, and this is a good way to jazz up frozen ones.

For this soup, you're going to start by slowly sautéing some sliced leek, for a subtle, sweet onion flavor. Celery and carrots cook alongside, getting sweeter as they soften over the low heat, and infusing the olive oil with flavor. Fresh thyme is one of the twiggy herbs, and it gives up its minty, earthy flavor in the warm oil, too.

Once that flavor base is built, you are ready to add the star of the season, asparagus. Because the stems cook more slowly than the delicate tips, I always lop off the tough bases, then chop the remaining stems. They can simmer in the stock until tender, and infuse the whole soup with that distinctive asparagus flavor. Last in are the tender tips, which only need a few minutes to cook.

Enjoy this fresh, French and flavorful dish for a satisfying spring meal.

Robin Asbell is a cooking instructor and author of "Big Vegan," "The Whole Grain Promise" and "Great Bowls of Food." Find her at robinasbell.com.