Instant Pot Sourdough Turmeric Coconut Lentil Soup with Crispy Bread

Name: Instant Pot Sourdough Turmeric Coconut Lentil Soup with Crispy Bread
Prep time: 15 min
Cook time: 25 min
Total time: 40 min
Yield: 6 servings
Cuisine: Indian
Ingredients: 1½ cups (300 g) red lentils, rinsed, rinsed under cold water; 1½ cups (1 can) (400 ml) unsweetened full-fat coconut milk; 4 cups (960 ml) vegetable or chicken broth; ½ cup (120 ml) active sourdough starter, at room temperature, bubbly and recently fed (1–4 hours after feeding); 1 whole (150 g) yellow onion, medium, finely diced; 2 tablespoons (18 g) fresh ginger, peeled, minced; 4 cloves (20 g) garlic cloves, minced; 2 teaspoons (10 g) ground turmeric; 1½ teaspoons (7 g) ground cumin; 1 teaspoon (5 g) ground coriander; to taste sea salt; to taste freshly ground black pepper; 2 tablespoons (30 ml) extra virgin olive oil; 2 tablespoons (30 ml) fresh lime juice (optional); ¼ cup (8 g) fresh cilantro, leaves, roughly chopped (optional); 4 oz (115 g) sourdough bread, day-old or stale, cut into ½-inch cubes; 1 tablespoon (15 ml) olive oil, for tossing; ¼ teaspoon (1½ g) sea salt, for croutons

From the MyKitchenBank Kitchen

A warmly spiced Indian-inspired lentil soup enriched with sourdough starter for subtle fermented depth and coconut milk for creaminess. The sourdough starter adds a gentle tang and helps break down the lentils for better digestibility, while turmeric, ginger, and cumin create aromatic complexity. Served with crispy sourdough bread cubes for texture and soul-warming comfort in every bowl.

Prep: 15 min
Cook: 25 min
Wait: 10 min
Total: 50 min
Makes: 6 servings (about 8 cups soup)

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Ingredients

6 servings

For the soup
1½ cups (300 g) red lentils, rinsed, rinsed under cold water
1½ cups (1 can) (400 ml) unsweetened full-fat coconut milk
4 cups (960 ml) vegetable or chicken broth
½ cup (120 ml) active sourdough starter, at room temperature, bubbly and recently fed (1–4 hours after feeding)
1 whole (150 g) yellow onion, medium, finely diced
2 tablespoons (18 g) fresh ginger, peeled, minced
4 cloves (20 g) garlic cloves, minced
2 teaspoons (10 g) ground turmeric
1½ teaspoons (7 g) ground cumin
1 teaspoon (5 g) ground coriander
to taste sea salt
to taste freshly ground black pepper
2 tablespoons (30 ml) extra virgin olive oil
For serving
2 tablespoons (30 ml) fresh lime juice (optional)
¼ cup (8 g) fresh cilantro, leaves, roughly chopped (optional)
For crispy bread topping
4 oz (115 g) sourdough bread, day-old or stale, cut into ½-inch cubes
1 tablespoon (15 ml) olive oil, for tossing
¼ teaspoon (1.5 g) sea salt, for croutons

Equipment (7)

Instant Pot or electric pressure cooker (6-quart capacity)
Measuring cups and spoons
Cutting board
Chef's knife
Wooden spoon
Baking sheet
Small bowl

Steps

Before you start

Have your Instant Pot on hand with the trivet included
Measure out active sourdough starter at room temperature (recently fed, bubbly)
Slice sourdough bread and cut into ½-inch cubes for the croutons
Gather all spices before starting

1
Make crispy croutonsOven 400°F / 205°C
- Preheat oven to 400°F (200°C).
- In a small bowl, toss the sourdough bread cubes with 1 tablespoon olive oil and ¼ teaspoon salt.
- Spread on a baking sheet in a single layer.
- Bake for 8–10 minutes, stirring halfway through, until golden and crispy on the edges.
- Set aside.
- (You can do this while the Instant Pot cooks.)
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Ready when: Croutons are golden brown and crispy at the edges
Tip: Use stale or day-old sourdough for the crispest croutons; fresh bread will be chewier.
2
Sauté aromatics
- Turn the Instant Pot to sauté mode on medium-high heat.
- Add 2 tablespoons olive oil.
- Once shimmering, add the diced onion and cook for 3–4 minutes, stirring occasionally, until soft and starting to turn translucent.
- Add the minced ginger and garlic, and stir constantly for 1 minute until fragrant.
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Ready when: Onion is soft and translucent; ginger and garlic are fragrant
Tip: Don't skip this step—sautéing builds the flavor foundation for the soup.
3
Toast spices
- Add the turmeric, cumin, and coriander to the pot.
- Stir constantly for 30 seconds to 1 minute, until fragrant and the spices coat the onion mixture.
- You'll notice the aroma intensify—that's when they're bloomed.
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Ready when: Spices are fragrant and evenly distributed; color deepens slightly
Tip: Toast the spices briefly to unlock their oils and deepen the flavors—this step makes a noticeable difference.
4
Add liquids and lentils
- Pour in the rinsed red lentils, vegetable broth, and coconut milk.
- Stir in the sourdough starter until well combined, breaking up any clumps.
- The mixture will be mostly liquid with lentils suspended throughout.
- Deglaze the bottom of the pot by scraping with a wooden spoon to release any stuck spices.
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Ready when: All ingredients are combined and bottom of pot is clear
Tip: Scraping the bottom prevents burning and ensures all the caramelized flavors distribute throughout the soup.
5
Pressure cook
- Close the Instant Pot lid and set the valve to sealing.
- Press the pressure cook button and set for 10 minutes on high pressure.
- The Instant Pot will take 3–4 minutes to build pressure, then cook for 10 minutes.
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Ready when: Pressure indicator shows pressure is reached, then cooking time elapses
Tip: Don't open the lid during cooking—the pressure is what makes the lentils break down so quickly.
6
Natural release and finish
- When the timer beeps, turn off the Instant Pot and let the pressure release naturally for 10 minutes.
- (The valve will stay at sealing during this time.) After 10 minutes, carefully turn the valve to venting to release any remaining pressure.
- Open the lid and stir the soup.
- It should be creamy and the lentils completely soft.
- Season with salt and black pepper to taste.
- If too thick, stir in ¼ to ½ cup additional broth or water.
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Ready when: Pressure is fully released; lentils are completely soft and break apart easily when stirred
Tip: Natural release is gentler and prevents the soup from splattering when you open the lid.
7
Serve with toppings
- Ladle the soup into bowls.
- Top each bowl with a generous handful of crispy croutons and a small pinch of fresh cilantro if desired.
- Offer lime juice on the side for each diner to add to taste.
- The croutons should be served fresh and crispy; they'll soften as they sit in the soup.
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Tip: Add croutons just before serving for maximum crispness; if you place them in the bowl too early, they'll absorb the soup and lose their texture.

Good to know

Tips

Active sourdough starter (fed 1–4 hours ahead) works best because it's bubbly and active. If your starter is sluggish, feed it and let it sit for 4–6 hours before using.
Red lentils break down completely in the Instant Pot, creating a naturally creamy soup without any blending needed. If you prefer a chunkier texture, use brown or green lentils and increase pressure cooking time to 15 minutes.
The sourdough starter adds a subtle fermented complexity and helps break down the starches in the lentils, making the soup easier to digest. It also slightly acidifies the soup, which brightens all the spices.
Make the crispy croutons while the Instant Pot is cooking under pressure so everything finishes around the same time—no extra steps or timing juggling.

Make ahead

You can prepare the soup up to 2 days ahead and store it in an airtight container in the fridge. Do not add the crispy croutons until just before serving. Reheat gently on the stovetop over medium heat, stirring occasionally, until warmed through (about 5–7 minutes). Make the crispy croutons fresh on the day of serving for the best texture.

Storage & reheating

Store the soup in an airtight container in the refrigerator for up to 3 days. Freeze in freezer-safe containers for up to 2 months (the sourdough starter and lentils freeze well). Thaw overnight in the fridge and reheat gently on the stovetop or in the Instant Pot using sauté mode. Crispy croutons are best stored in an airtight container at room temperature for up to 1 day; rewarm in a 300°F (150°C) oven for 3–4 minutes before serving if they soften.

Substitutions

red lentils, rinsed → yellow lentils or split peas. Use the same quantity. Yellow lentils will also break down completely; split peas may take 1–2 minutes longer to fully soften.
unsweetened full-fat coconut milk → heavy cream or full-fat Greek yogurt. Use 1.5 cups cream and omit sourdough starter, or stir in ½ cup Greek yogurt after cooking instead of adding it at the start to prevent curdling.
active sourdough starter, at room temperature → plain yogurt or buttermilk. Use the same quantity (½ cup). The tang will be similar, though yogurt or buttermilk won't add the fermented depth sourdough starter does.
sourdough bread, day-old or stale → any crusty bread (French, Italian, or whole grain). Use stale or toasted slices for crispness. Regular soft bread will not crisp as well; fresh bread can be lightly toasted before cubing.