Name: Grandma's Lentil Soup
Prep time: 15 min
Cook time: 35 min
Total time: 50 min
Cuisine: Mediterranean
Ingredients: 2 tablespoons olive oil; 1 medium yellow onion finely diced; 3 medium carrots peeled and diced; 2 celery stalks diced; 3 garlic cloves minced; 2 tablespoons tomato paste; 1 1⁄2 teaspoons ground cumin; 1 teaspoon smoked paprika; 1 teaspoon dried thyme; 1 1⁄2 cups brown or green lentils rinsed and drained; 2 medium gold potatoes peeled and diced into small cubes; 1 can 14.5 ounces diced tomatoes with juices; 6 cups low sodium vegetable broth; 1 cup water plus more as needed; 2 bay leaves; 1 1⁄2 teaspoons fine sea salt plus more to taste; 3⁄4 teaspoon freshly ground black pepper; 1⁄4 teaspoon crushed red pepper flakes optional; 1⁄4 cup chopped fresh parsley plus more for serving; 2 tablespoons fresh lemon juice

I grew up believing that a pot of lentils on the stove could fix just about anything—from cold winter nights to rough school days. Grandma’s Lentil Soup was the smell that greeted me when I walked into her kitchen: tomatoey steam fogging up the windows, carrots and potatoes bobbing to the surface, and that cozy mix of garlic and herbs that made everyone linger a little longer around the table.

This version is my loving recreation of her recipe—simple, hearty, and surprisingly wholesome. It’s built on everyday pantry staples, but the slow simmer and a splash of bright lemon at the end make it taste like you’ve been cooking all day. Whether you need an easy weeknight dinner or a big batch of make-ahead lunches, this lentil soup has you covered.

What Makes Grandma’s Lentil Soup So Special?

For me, it’s all about the balance. The lentils stay tender but not mushy, the carrots and potatoes add sweetness and body, and the tomatoes bring a gentle tang that keeps every spoonful interesting. A warm blend of cumin, smoked paprika, and thyme gives the broth depth without making it feel heavy.

It’s also endlessly practical. This soup is naturally high in fiber and plant-based protein, budget-friendly, and perfect for feeding a crowd. It freezes beautifully, so one relaxed cooking session can turn into several quick lunches or dinners later in the week.

Ingredients for Grandma’s Lentil Soup

Instead of a long, intimidating list, think of these ingredients as a team—each one playing a role in building flavor and texture:

Olive oil – Helps the onions, carrots, and celery soften and caramelize slightly, creating the flavorful base Grandma always insisted on.

Yellow onion – The quiet backbone of the soup, adding sweetness and savory depth as it cooks down.

Carrots – Bring natural sweetness and a bit of color; they also hold their texture well during the simmer.

Celery – Adds an herby, aromatic note that rounds out the classic soup trio.

Garlic cloves – Grandma never measured, she just said “enough to smell good.” Garlic brings warmth and richness to every spoonful.

Tomato paste – Concentrated tomato flavor that gives the broth its deep color and savory, almost meaty taste.

Diced tomatoes – Add tang, juiciness, and little bursts of tomato in the finished soup.

Brown or green lentils – Sturdy lentils that keep their shape, soak up the seasoning, and make the soup hearty and filling.

Potatoes – Tender cubes of potato give the soup body and make it feel like a complete meal in a bowl.

Vegetable broth – Forms the base of the soup; using a good-quality broth keeps the flavor rich even without meat.

Water – Used to adjust the thickness of the soup without overpowering the seasoning.

Ground cumin – Adds a gentle earthiness and warmth that makes the lentils taste deeper and more complex.

Smoked paprika – Brings a subtle smoky note that mimics the flavor of long, slow cooking.

Dried thyme – A classic herb that pairs beautifully with tomatoes, lentils, and potatoes.

Bay leaves – Infuse the broth with a delicate herbal aroma while the soup simmers.

Salt and black pepper – Essential for waking up all the other flavors; you’ll adjust these at the end to match your taste.

Crushed red pepper flakes (optional) – Just a pinch adds a gentle kick that keeps the soup from feeling flat.

Fresh parsley – Stirred in at the end for freshness and a pop of color on top.

Fresh lemon juice – A squeeze of lemon right before serving brightens the entire pot and makes the flavors come alive.

How To Make Grandma’s Lentil Soup

Step 1: Build the Flavor Base

I start by warming a generous swirl of olive oil in a large heavy-bottomed pot over medium heat. In go the diced onion, carrots, and celery with a pinch of salt. I let them soften slowly for about 8–10 minutes, stirring every now and then, until the onions look translucent and the edges of the carrots just begin to turn golden. This step is where the backbone of the soup is built, so don’t rush it.

Once the vegetables are soft, I add the minced garlic and cook it for about 30 seconds, just until it smells fragrant. You don’t want it to brown—burnt garlic will make the soup taste bitter.

Step 2: Toast the Tomato Paste and Spices

Next, I stir in the tomato paste, cumin, smoked paprika, and dried thyme. The tomato paste should darken slightly as it cooks; this takes 1–2 minutes and gives it a deeper, almost caramelized flavor. Toasting the spices in the oil wakes them up and helps them bloom into the broth instead of tasting raw.

Step 3: Add Lentils, Potatoes, and Broth

Now it’s time to turn everything into soup. I add the rinsed lentils, diced potatoes, the can of diced tomatoes with their juices, bay leaves, vegetable broth, and a bit of water. I give everything a good stir, scraping up any browned bits from the bottom of the pot—Grandma always said those bits were “where the flavor hides.”

I bring the mixture up to a boil, then immediately lower the heat so it’s just gently simmering. With the lid slightly ajar, the soup cooks for about 30–35 minutes, until the lentils are tender but not falling apart and the potatoes are soft.

Step 4: Adjust the Texture and Seasoning

Once the lentils and potatoes are cooked, I like to tweak the texture a bit. If the soup looks too thick, I splash in a little more water or broth. If it feels too thin, I use a ladle to scoop out a cup or two of the soup, quickly mash it with a fork or potato masher, and stir it back in. This gives the broth a naturally creamy feel without adding any dairy.

I remove the bay leaves, then season the soup with salt, black pepper, and a pinch of red pepper flakes if I’m in the mood for a gentle heat. This is the moment to taste and adjust until it makes you want to go in for another spoonful.

Step 5: Finish With Freshness

Right before serving, I stir in a handful of chopped fresh parsley and a good squeeze of lemon juice. That little hit of acidity brightens all the cozy flavors and keeps the soup from feeling heavy. I save a bit of parsley to sprinkle over each bowl for a fresh, homemade touch.

Serving and Storing Grandma’s Lentil Soup

When the soup is ready, I ladle it into warm bowls and finish each one with an extra drizzle of olive oil, a sprinkle of parsley, and plenty of freshly cracked black pepper. It’s wonderfully filling on its own, but a slice of crusty bread or a simple salad beside it never hurts.

This soup actually tastes even better the next day, once the lentils have soaked up more of the flavorful broth. Let leftovers cool completely, then store them in airtight containers in the refrigerator for up to 4 days.

For longer storage, Grandma’s Lentil Soup freezes like a dream. I portion it into freezer-safe containers or bags, label them, and freeze for up to 3 months. To reheat, thaw overnight in the fridge if you can, then warm gently on the stovetop with a splash of water or broth to loosen the texture.

What to Serve With Grandma’s Lentil Soup?

Crusty Bread or Garlic Toast

A warm, crusty baguette or thick slices of garlic toast are perfect for dunking into the thick, savory broth.

Simple Green Salad

A light salad with mixed greens, cherry tomatoes, cucumbers, and a lemony vinaigrette balances the richness of the soup.

Grilled Cheese Sandwich

If you want to turn this into the coziest dinner ever, pair a steaming bowl of lentil soup with a gooey grilled cheese—Grandma’s favorite combo.

Roasted Vegetables

Roasted broccoli, Brussels sprouts, or carrots add extra veggies to the plate and bring a little charred sweetness that works beautifully with the earthy lentils.

Rice or Quinoa

Spoon the soup over a scoop of fluffy rice or quinoa to stretch it even further and make it extra hearty.

Simple Herb Flatbread

Soft, warm flatbread brushed with olive oil and sprinkled with herbs is another great way to mop up every last drop.

Want More Cozy Soup Ideas?

If you love the comfort of Grandma’s Lentil Soup, you’ll probably enjoy these other warm, spoon-worthy favorites from around my kitchen:

A Hearty Bowl of Comfort Tuscan Bean Soup for another rustic, bean-packed classic.
Creamy Broccoli Cheddar Soup when you’re craving something extra cheesy and velvety.
Italian Sausage Soup for a meatier option with bold, savory flavor.
20-Minute Broccoli Cheese Soup for those nights when you need cozy comfort in a hurry.

Save This Pin For Later

📌 Save this Grandma’s Lentil Soup to your favorite soup or dinner board on Pinterest so you can find it quickly the next time you’re craving something warm and nourishing.

When you make it, I’d love to hear how it turned out for you. Did you add extra veggies, use a different kind of lentil, or spice it up with more heat? Share your tweaks and questions in the comments so we can keep improving this family favorite together.

For even more cozy dinners, simple lunches, and comforting soups, explore my daily recipe pins over on ChefAlchemy’s Pinterest page and discover your next go-to bowl of comfort.