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Carabaccia (Tuscan Onion Soup)

By Annie Petito

Published on February 5, 2024

Time

1 ¼ hours

Yield

Serves 4

Carabaccia (Tuscan Onion Soup)

Ingredients

2 pounds red onions, halved and sliced through root end ¼ inch thick5 cups water, divided 3 tablespoons extra-virgin olive oil, divided ¾ teaspoon table salt, divided 2 sprigs fresh sage 1 bay leaf ½ cup (1 ounce) finely grated Parmesan cheese, plus extra for serving4 poached eggs 4 (½-inch-thick) slices thick-crusted country bread

Before You Begin

Carabaccia is traditionally made with water but feel free to use your favorite chicken or vegetable broth in step 2. A rasp grater works well for grating the Parmesan. We like to serve this soup with a poached egg spooned on top of the toast before the soup is ladled into the bowl. Our Perfect Poached Eggs recipe works great here; make the eggs while the soup simmers. 

Instructions

  1. Bring onions, 1 cup water, 2 tablespoons oil, and ½ teaspoon salt to boil in Dutch oven over high heat. Adjust heat to medium, cover, and cook at rapid simmer, stirring occasionally, until onions have fully softened and collapsed, 18 to 20 minutes. Uncover and continue to cook, stirring occasionally, until liquid evaporates (onions should not brown), 6 to 8 minutes. (Onions can be refrigerated for up to 3 days or frozen for up to 1 month.)
  2. Add sage sprigs, bay leaf, remaining 4 cups water, and remaining ¼ teaspoon salt. Bring to boil, adjust heat to gentle simmer and cook, covered, for 30 minutes. Remove sage sprigs and bay leaf. Stir in Parmesan. Season with salt and pepper to taste. 
  3. Meanwhile, adjust oven rack about 6 inches from broiler element and heat broiler. Place bread on aluminum foil-lined rimmed baking sheet, drizzle with remaining 1 tablespoon oil and season with salt and pepper. Broil until browned, crisp, and starting to char at edges, 2 to 4 minutes. Flip bread and continue to broil until bottom is starting to char, 2 to 4 minutes longer.
  4. Place 1 slice bread in bottom of each individual bowl. Top bread with poached egg. Ladle soup into bowl. Serve, passing Parmesan separately. 

Carabaccia (Tuscan Onion Soup)

Save

Time

1 ¼ hours

Yield

Serves 4

Ingredients

2 pounds red onions, halved and sliced through root end ¼ inch thick
5 cups water, divided
3 tablespoons extra-virgin olive oil, divided
¾ teaspoon table salt, divided
2 sprigs fresh sage
1 bay leaf
½ cup (1 ounce) finely grated Parmesan cheese, plus extra for serving
4 poached eggs
4 (½-inch-thick) slices thick-crusted country bread

Test Kitchen Techniques

Ingredients

2 pounds red onions, halved and sliced through root end ¼ inch thick
5 cups water, divided
3 tablespoons extra-virgin olive oil, divided
¾ teaspoon table salt, divided
2 sprigs fresh sage
1 bay leaf
½ cup (1 ounce) finely grated Parmesan cheese, plus extra for serving
4 poached eggs
4 (½-inch-thick) slices thick-crusted country bread

Test Kitchen Techniques

Ingredients

2 pounds red onions, halved and sliced through root end ¼ inch thick
5 cups water, divided
3 tablespoons extra-virgin olive oil, divided
¾ teaspoon table salt, divided
2 sprigs fresh sage
1 bay leaf
½ cup (1 ounce) finely grated Parmesan cheese, plus extra for serving
4 poached eggs
4 (½-inch-thick) slices thick-crusted country bread

Test Kitchen Techniques

Why This Recipe Works

Carabaccia is a simple, centuries-old Tuscan onion soup made by softening (but not browning) and then simmering loads of onions in water until the liquid is gently savory-sweet; the soup is served with toasted bread, grated Parmesan or Pecorino, and perhaps a poached egg. For our take, we softened 2 pounds of thin-sliced red onions by first simmering them covered, with a little water, salt, and olive oil, so that the moist heat would encourage them to quickly collapse. Then we briefly cooked them uncovered to evaporate the liquid and concentrate their flavor; we finally simmered them with water, sage, and bay leaf to infuse the broth with the onions' sweet savor. Stirring grated Parmesan into the soup enhanced its flavor. While the soup simmered, we broiled slices of crusty bread and poached eggs. To serve, we placed a slice of toast in each bowl; topped it with a poached egg; and ladled the soup around the bowl.

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Before You Begin

Carabaccia is traditionally made with water but feel free to use your favorite chicken or vegetable broth in step 2. A rasp grater works well for grating the Parmesan. We like to serve this soup with a poached egg spooned on top of the toast before the soup is ladled into the bowl. Our Perfect Poached Eggs recipe works great here; make the eggs while the soup simmers. 

Instructions

  1. Bring onions, 1 cup water, 2 tablespoons oil, and ½ teaspoon salt to boil in Dutch oven over high heat. Adjust heat to medium, cover, and cook at rapid simmer, stirring occasionally, until onions have fully softened and collapsed, 18 to 20 minutes. Uncover and continue to cook, stirring occasionally, until liquid evaporates (onions should not brown), 6 to 8 minutes. (Onions can be refrigerated for up to 3 days or frozen for up to 1 month.)
  2. Add sage sprigs, bay leaf, remaining 4 cups water, and remaining ¼ teaspoon salt. Bring to boil, adjust heat to gentle simmer and cook, covered, for 30 minutes. Remove sage sprigs and bay leaf. Stir in Parmesan. Season with salt and pepper to taste. 
  3. Meanwhile, adjust oven rack about 6 inches from broiler element and heat broiler. Place bread on aluminum foil-lined rimmed baking sheet, drizzle with remaining 1 tablespoon oil and season with salt and pepper. Broil until browned, crisp, and starting to char at edges, 2 to 4 minutes. Flip bread and continue to broil until bottom is starting to char, 2 to 4 minutes longer.
  4. Place 1 slice bread in bottom of each individual bowl. Top bread with poached egg. Ladle soup into bowl. Serve, passing Parmesan separately. 

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