Three-Bean Salad Soup

The idea of turning a cold picnic salad into soup struck me during one of those rainy spring afternoons when the garden was too muddy to harvest but I was craving something garden-fresh. I stared at the three-bean salad I'd prepped earlier, that bright medley of red onion and peppers, and thought: what if this could warm you up instead? The first batch was an experiment that had my kitchen smelling like vinegar and hope. Now it's become the soup I make when I want comfort food that still feels bright and alive.

Last summer my neighbor came over while this was bubbling away on the stove. She kept asking what I was making because the vinegar and garlic had drifted into her yard. We ended up eating it on her back porch with torn pieces of crusty bread, and she made me write the recipe on a napkin before she let me leave. Now she makes it every time her daughter visits from college.

Ingredients

• Canned kidney beans: These hold their shape beautifully and bring that classic earthy sweetness that grounds the whole soup
• Cannellini beans: Creamy and mild, they're the soft counterpoint to the firmer kidney beans and absorb the vinaigrette flavors perfectly
• Green beans: Fresh or canned, they add crucial texture and that snap that reminds you this started as a salad
• Red bell pepper: Dice them small so they soften but don't disappear, adding pockets of sweetness throughout
• Red onion: Finely chopped is key here so you get flavor without harsh crunchy bites
• Garlic: Two cloves might feel modest but since they're sautéed not roasted, their flavor stays present and sharp
• Red wine vinegar: The soul of this recipe, use a good quality one because its the backbone of that salad flavor profile
• Dijon mustard: Just enough to give the broth body and a slight edge that keeps each spoonful interesting
• Vegetable broth: Low-sodium lets you control the seasoning, and the mild base lets those vinaigrette flavors shine

Instructions

Build your aromatic base:

Heat olive oil in your large soup pot over medium heat. Add the onion, celery, and garlic, letting them soften and become fragrant for about 3 to 4 minutes.

Add the colorful vegetables:

Stir in the diced red bell pepper and cook for another 2 minutes until it just starts to yield to the spoon.

Introduce all three beans:

Add kidney beans, cannellini beans, green beans, and halved cherry tomatoes. Let everything sauté together briefly, just 1 to 2 minutes, so the beans start absorbing those aromatic flavors.

Create the soup base:

Pour in vegetable broth and bring it to a gentle boil. Meanwhile, whisk together red wine vinegar, Dijon mustard, sugar, oregano, and red pepper flakes in a small bowl.

Let it meld and deepen:

Stir the vinaigrette mixture into the pot, reduce heat to a simmer, and cook uncovered for 15 minutes. The broth will transform into something rich and tangy.

Finish with fresh brightness:

Season with salt and pepper to taste, then stir in chopped parsley. Ladle into bowls and garnish with extra parsley if you're feeling fancy.

Save

My sister-in-law initially wrinkled her nose at bean soup until she tasted this version. Now she texts me photos whenever she makes it, usually with some variation she discovered. Last week she added a splash of balsamic and swore it changed everything.

Making It Your Own

Sometimes I'll throw in a handful of spinach or kale during the last two minutes of simmering. The greens wilt into the broth and make it feel even more substantial without changing the fundamental character of the soup.

The Bread Question

Crusty sourdough is my go-to because the tang mirrors the vinaigrette base. But honestly, a simple slice of buttered toast or even crackers will work when you need something to soak up that last bit of broth from the bottom of the bowl.

Serving Suggestions

This soup strikes that perfect balance between light and satisfying, making it ideal for lunch or a casual dinner. I like to set out small bowls of extra red pepper flakes and grated Parmesan so people can customize their bowls.

• Let guests add their own finishing touches at the table
• Serve with a wedge of lemon for those who love extra brightness
• Keep some crusty bread nearby for the essential broth-dipping ritual

Save

There's something almost magical about taking familiar flavors and arranging them in a way that feels completely new yet comfortingly familiar. This soup has become my go-to for rainy days and unexpected guests alike.

Recipe FAQs

→ Can I use dried beans instead of canned?

Yes, soak and cook ½ cup each of dried kidney and cannellini beans until tender before adding. For fresh green beans, trim and cut into 1-inch pieces, then blanch for 2-3 minutes before adding to the soup.

→ Is this soup served hot or cold?

This version is designed to be served hot or warm. However, the vinaigrette flavors make it excellent chilled—simply cool completely and refrigerate for at least 4 hours before serving cold.

→ How long does this soup keep in the refrigerator?

Stored in an airtight container, this soup keeps well for 4-5 days. The vinaigrette flavors actually deepen and improve after a day or two. Reheat gently on the stovetetop.

→ Can I make this dish vegan?

The soup is naturally vegan as written. Just ensure your Dijon mustard doesn't contain honey or other animal products. The broth should be vegetable-based.

→ What other vegetables work well in this soup?

Zucchini, yellow squash, diced carrots, or fresh corn kernels all complement the beans beautifully. Add heartier vegetables like carrots with the onions, and tender vegetables like zucchini or corn during the last 5-10 minutes of simmering.