Vegetarian French Onion Soup With Asparagus & Cheesy Croutons

Author Notes

When I think of eating French onion soup, or soupe à l’oignon (gratinée, if topped with bread and cheese, which it nearly always is), I see myself in a tiny Parisian café on a frigid winter afternoon, sipping on a vermouth (Dolin Blanc, one rock, with a twist, thank you so much) in between slurps of the steaming-hot soup. Idyllic as it sounds, that’s not quite the vibe once the weather starts to thaw, and the crisp green vegetables start to replace potatoes and onions for prime spots at the farmers market. (Except for the vermouth part. That’s my drink year-round.) Yet, on spring evenings that slant chilly, there’s still a place in my heart for a warm bowl of soup. Just something a tad fresher. Which brings me to the task at hand: vegetarian French onion soup.

In Mastering the Art of French Cooking, Julia Child’s recipe (a traditional French onion soup if ever there was one) calls for heavy beef stock mixed with caramelized onions, as well as a few tablespoons of flour to thicken the brew. In the interest of budget and simplicity, I forgo stock altogether, relying on even more deeply browned, Maillarded-to-the-max onions (two and a half pounds of them to be exact, about $2.50). When seasoned well and mixed with water, they create their own deeply flavorful, totally vegan stock. For a little flavor help, add a splash of Worcestershire (buy a vegan version or use soy sauce if you’re strictly vegetarian) if you’d like.

Child’s soup is fortified with white wine or dry vermouth, plus a bit of granulated sugar to assist with browning the onions; while I don’t think sugar is truly necessary to brown the onions, it does add flavor, emphasizing onions’ already naturally strong sweetness. Good vermouth—you’ll need about a buck’s worth here—is always cheaper than good wine, and it lasts longer to boot, so that’s a natural addition to this recipe. (Though I don’t call for sugar here, you could use sweet vermouth, blanc or rouge, instead of dry, to channel Child’s sweeter-slanting recipe.)

Onion soup gratinée comes topped with a thick hunk of bread and practically a block of brûléed Gruyère, Swiss, or Comté, which is perfect, but far too wintry for this variation. Instead, we’ll make smaller, crispier croutons from whatever crusty bread you have on hand ($3), covered in a slightly less generous blanket of sharp Cheddar ($1.50).

To fully remind us that spring has sprung, in a wildly nontraditional gesture, just before serving the soup, I stir in fresh asparagus (more affordable when in season, about $2!), which turns the absolute brightest shade of green when it hits the soup. As Child would say, Bon appétit!
—Rebecca Firkser

Test Kitchen Notes

Nickel & Dine is a budget column by Rebecca Firkser, assigning editor at Food52 and defender of vermouth. Each month, Rebecca will share an easy, flavor-packed recipe that feeds four (or just you, four times)—all for $10 or less. —The Editors