Italian Lentil Soup with Roasted Fennel and Orange Zest

Name: Italian Lentil Soup with Roasted Fennel and Orange Zest
Prep time: 20 min
Cook time: 57 min
Total time: 1 h 17 min
Yield: 6 servings
Cuisine: Italian
Ingredients: 2 bulbs (about 1.5 lb total) (700 g) large fennel bulbs, stalks trimmed off, fronds reserved for garnish, bulbs cut lengthwise into ½-inch (1.25 cm) thick wedges with a bit of core left attached to each wedge; 3 tbsp (45 ml) extra-virgin olive oil; ½ tsp (3 g) kosher salt; 3 tbsp (45 ml) extra-virgin olive oil; 1 medium (about 7 oz) (200 g) yellow onion, cut into ¼-inch (6 mm) dice; 2 medium (about 5 oz) (150 g) carrots, peeled and cut into ¼-inch (6 mm) dice; 2 medium (about 3.5 oz) (100 g) celery ribs, cut into ¼-inch (6 mm) dice; 4 cloves (14 g) garlic cloves, finely minced; 2 tbsp (32 g) tomato paste; 2 tsp (3 g) fresh rosemary leaves, finely chopped; 1½ cups (300 g) Castelluccio lentils, rinsed and drained; 6 cups (1420 ml) low-sodium vegetable broth; 1 cup (240 ml) water; 1 leaf (1 g) dried bay leaf; 1 piece (about 2 inches) (30 g) Parmesan rind, scrubbed clean (optional); 1 tsp, plus more to taste (6 g) kosher salt; black pepper, freshly ground, to taste; 1 large (250 g) large orange, scrubbed; zest removed in fine strips or finely grated (about 2 tsp), then juiced (about 3 tbsp); 1 tbsp (15 ml) red wine vinegar; 2 tbsp (30 ml) extra-virgin olive oil, for drizzling; ½ cup (40 g) Parmigiano-Reggiano, finely grated (optional)

From the MyKitchenBank Kitchen

Earthy Castelluccio lentils simmer with a soffritto of onion, carrot and celery, garlic and rosemary. Caramelized roasted fennel gives the soup sweetness, and fresh orange zest and a splash of vinegar make it taste bright. Castelluccio lentils need no soaking and hold their shape, so the soup is hearty and quick to make.

Prep: 20 min
Cook: 57 min
Wait: 5 min
Total: 1 hr 22 min
Makes: About 2.5 quarts (2.4 L), 6 generous bowls

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Ingredients

6 servings

For the roasted fennel
2 bulbs (about 1.5 lb total) (700 g) large fennel bulbs, stalks trimmed off, fronds reserved for garnish, bulbs cut lengthwise into ½-inch (1.25 cm) thick wedges with a bit of core left attached to each wedge
3 tbsp (45 ml) extra-virgin olive oil
½ tsp (3 g) kosher salt
For the soup
3 tbsp (45 ml) extra-virgin olive oil
1 medium (about 7 oz) (200 g) yellow onion, cut into ¼-inch (6 mm) dice
2 medium (about 5 oz) (150 g) carrots, peeled and cut into ¼-inch (6 mm) dice
2 medium (about 3.5 oz) (100 g) celery ribs, cut into ¼-inch (6 mm) dice
4 cloves (14 g) garlic cloves, finely minced
2 tbsp (32 g) tomato paste
2 tsp (3 g) fresh rosemary leaves, finely chopped
1½ cups (300 g) Castelluccio lentils, rinsed and drained
6 cups (1420 ml) low-sodium vegetable broth
1 cup (240 ml) water
1 leaf (1 g) dried bay leaf
1 piece (about 2 inches) (30 g) Parmesan rind, scrubbed clean (optional)
1 tsp, plus more to taste (6 g) kosher salt
black pepper, freshly ground, to taste
To finish
1 large (250 g) large orange, scrubbed; zest removed in fine strips or finely grated (about 2 tsp), then juiced (about 3 tbsp)
1 tbsp (15 ml) red wine vinegar
2 tbsp (30 ml) extra-virgin olive oil, for drizzling
½ cup (40 g) Parmigiano-Reggiano, finely grated (optional)

Equipment (7)

Large rimmed baking sheet, 18×13 inches (46×33 cm)
Parchment paper
5- to 6-quart (4.7–5.7 L) Dutch oven or heavy soup pot
Fine-mesh sieve
Microplane or fine grater
Immersion blender or countertop blender (optional)
Wooden spoon and ladle

Steps

Before you start

Position an oven rack in the center and preheat the oven to 425°F (220°C) while you chop.
Rinse the lentils in a fine-mesh sieve and pick out any small stones or debris. Castelluccio lentils do not need soaking.
The fennel roasts while the soup base cooks, so have both the baking sheet and the Dutch oven ready before you start.
Zest the orange before you juice it. Juiced oranges are very hard to zest.

1
Prep the vegetablesOven 425°F / 220°C
- Preheat the oven to 425°F (220°C) with a rack in the center.
- Trim the fennel stalks, set aside a small handful of feathery fronds, and cut each bulb lengthwise into ½-inch wedges, keeping a bit of core on each wedge so it holds together.
- Dice the onion, carrot and celery into ¼-inch pieces, mince the garlic, chop the rosemary, and rinse the lentils.
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Ready when: Vegetables are in even, small dice so they cook at the same rate.
Tip: Uniform dice matter here because they soften at the same pace as the lentils.
2
Start roasting the fennelOven 425°F / 220°C
- Line a rimmed baking sheet with parchment.
- Toss the fennel wedges with 3 tbsp olive oil and ½ tsp salt, then spread in a single layer with space between them.
- Roast at 425°F (220°C) for 30 minutes, flipping the wedges once at 15 minutes.
- Start the soup base in the next step while the fennel roasts.
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Ready when: Fennel is tender when pierced with a knife and deeply golden with browned edges.
Tip: Crowding steams the fennel instead of browning it. Use two sheets if the wedges overlap.
3
Cook the soffritto
- Heat 3 tbsp olive oil in the Dutch oven over medium heat.
- Add the onion, carrot, celery and 1 tsp salt.
- Cook, stirring every minute or so, for 10 minutes.
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Ready when: The onion is translucent and soft, and the carrots are tender when pressed with the back of the spoon. Nothing should be browned.
Tip: If the vegetables begin to brown, lower the heat to medium-low.
4
Bloom garlic and tomato paste
- Stir in the garlic, rosemary and tomato paste.
- Cook, stirring constantly, for 2 minutes.
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Ready when: The tomato paste darkens to brick red, and the garlic and rosemary smell fragrant. The garlic should not be browned.
Tip: Burnt garlic turns bitter, so lower the heat if it starts to color.
5
Simmer the lentils
- Add the lentils, broth, water, bay leaf and Parmesan rind, if using.
- Raise the heat to high and bring to a boil.
- Reduce to medium-low so the soup simmers gently with small bubbles, partially cover, and cook for 30 minutes, stirring occasionally.
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Ready when: Lentils are tender all the way through but still hold their shape, with no chalky center when you bite one.
Tip: A hard boil breaks the lentils apart. Keep the simmer gentle.
6
Add the roasted fennel
- Remove the fennel from the oven.
- Set aside about half of the wedges for topping.
- Chop the rest into ½-inch pieces and stir them into the soup.
- Remove the bay leaf and Parmesan rind.
- Simmer uncovered for 5 minutes so the flavors blend.
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Ready when: The broth tastes slightly sweet and a little caramelized from the fennel.
Tip: Scrape any browned bits from the baking sheet into the pot. They add flavor.
7
Thicken the soup lightly
- Turn off the heat.
- Insert an immersion blender and pulse 4 or 5 times, only enough to break down about one quarter of the soup.
- Or ladle 1½ cups of soup into a blender, blend until smooth, and stir it back in.
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Ready when: The broth looks creamy and thicker, with plenty of whole lentils still visible.
Tip: If using a countertop blender, leave the lid vent open and cover it with a towel so steam can escape.
8
Brighten and season
- Stir in about 2 tsp orange zest, 3 tbsp orange juice and 1 tbsp red wine vinegar.
- Taste, then add salt and pepper until the soup tastes lively and the orange comes through without being sweet.
- Add up to ½ tsp more salt at a time.
- If the soup is too thick, thin it with ¼ cup (60 ml) hot water.
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Ready when: The soup tastes balanced: savory, slightly sweet and bright, with a citrus aroma.
Tip: Add zest and juice off the heat so the orange flavor stays fresh.
9
Rest and serve
- Let the soup rest, covered, for 5 minutes.
- Ladle it into warm bowls and top each with a few reserved fennel wedges, a drizzle of olive oil, torn fennel fronds, a little more orange zest if you like, and Parmigiano-Reggiano if using.
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Ready when: The soup is steaming hot but no longer bubbling, with a slightly thicker body.
Tip: Serve with crusty bread to mop up the broth.

Good to know

Tips

Roast the fennel until the edges turn dark golden brown. This is where the soup's sweetness comes from.
Add salt in stages, once to the soffritto and once at the end. Lentils taste flat without enough salt, but broths vary a lot.
Zest the orange with a Microplane, taking only the orange layer. The white pith is bitter.
Only blend a quarter of the soup. This gives a creamy broth while the whole lentils keep their texture.

Make ahead

"The soup tastes even better the next day. Make it through step 7, cool, and refrigerate. Reheat gently and add the orange zest, juice and vinegar (step 8) just before serving so they stay fresh. Roast the fennel garnish fresh, or re-crisp leftover wedges for 8 minutes at 425°F (220°C)."

Storage & reheating

"Room temperature: up to 2 hours. Refrigerator: store in an airtight container for up to 5 days. Freezer: freeze without the garnishes for up to 3 months, and thaw overnight in the fridge. Reheat in a pot over medium-low heat, stirring often, until steaming (about 10 minutes). Add a splash of water or broth, since the lentils keep absorbing liquid."

Substitutions

Castelluccio lentils → Umbrian or French green (Puy) lentils. Both hold their shape well. Start checking Puy lentils at 25 minutes. Brown lentils work too but break down more.
low-sodium vegetable broth → low-sodium chicken broth. Gives a richer flavor but makes the soup non-vegetarian. Adjust the salt to taste.
red wine vinegar → fresh lemon juice. Use 1 tbsp. The soup will taste a bit sharper.
fresh rosemary leaves → fresh thyme leaves. Use 1 tsp. Thyme is milder and tastes slightly more herbal.