Creamy Potato Soup Recipe

French

This creamy potato soup gets its depth from slow-caramelised onions, a quick deglaze, and a fragrant herb simmer.

Blend until silky, then finish with lemon and olive oil for a lighter, brighter bowl at home.

Creamy potato soup with caramelised onion

As soon as the weather turns cool, I slip into my favourite ritual: one velvety soup a week.

To keep it fun, I rotate the vegetables, and today it’s the dependable potato, the one that’s almost always in the cupboard.

What makes this bowl memorable isn’t anything fancy, but the small steps that build flavour.

I let the onions cook slowly until they’re deep golden and sweet, then deglaze the pot to lift every browned, savoury bit.

The potatoes simmer in a good broth with thyme, rosemary, and a bay leaf until they’re melt-in-your-mouth tender.

A quick blend turns everything silky, with no need for cream.

Right at the end, a squeeze of lemon brightens the sweetness and keeps the soup tasting light.

The original version I saw used white wine, but I often reach for balsamic vinegar for its gentle sweet-tang.

This time I only had white vinegar, which gave a paler colour and a clean, mellow finish, still absolutely comforting. Top with olive oil, herbs.

Potato Soup Ingredients and Substitutions

• Butter (2 tbsp) : Adds a rich, rounded base at the start of cooking.
  Dairy-free swap: ghee (closest flavour), olive oil (more fruity), or plant-based margarine (more neutral).
• Large onion (1, finely sliced – about 2½ – 3 cups) : The flavour foundation: the more you caramelise it, the deeper and “jammy” the soup tastes.
• Garlic (2 cloves, minced) : Stir in near the end of caramelising so it doesn’t burn; it should turn fragrant, not brown.
• Yukon Gold potatoes (680 g / 1½ lb, cut into 2.5 cm / 1-inch cubes – about 4 packed cups) : Naturally creamy once blended.
  Skin-on option: especially for new potatoes, scrub well before cutting.
  Alternative: Charlotte potatoes or any yellow-fleshed variety.
• Broth (4 cups) : Chicken bone broth gives extra depth, but regular chicken or vegetable broth works beautifully.
• Water (1-2 cups, as needed) : For adjusting texture after blending; more water = a lighter soup.
• White wine or vinegar (¼ cup, for deglazing) : Lifts the caramelised bits from the bottom of the pot for extra flavour.
  Balsamic: smoother, slightly sweet. White vinegar: brighter, sharper, paler colour.
• Kosher salt (1 tsp, then adjust) : Broths vary in saltiness, so fine-tune at the end.
• Ground black pepper (1 tsp) : Gentle warmth; tweak at serving if needed.
• Fresh rosemary + thyme (1 sprig each, plus extra to finish) : Infuse during simmering, then add a little fresh on top for a brighter aroma.
• Bay leaf (1) : Adds slow-cooked depth; remove before blending.
• Fresh lemon juice (1 tbsp) : The final lift that brightens the potatoes and balances richness.
• Extra-virgin olive oil (up to 4 tbsp, to serve, optional) : A drizzle makes a big difference: fruity contrast and a more luxurious finish.

Step-by-Step Method for Creamy Potato Soup

1) Melt the fats 

• Heat a Dutch oven over medium heat.
• Add the butter plus a small drizzle of oil, and warm until the butter is melted and foamy (that’s your signal to start cooking).

2) Caramelise the onion (your flavour base)

• Add the sliced onion, season with a small pinch of salt, and stir to coat.
• Cook, stirring about every 5 minutes, until it goes soft → golden → deep golden-brown.

If it sticks or dries out: add 1 tbsp water or broth, scrape the bottom, and keep going (you may use up to ~60 ml / ¼ cup total).

Ready cue: onions are soft, evenly deep golden-brown, and smell sweet and “jammy.”

3) Add the garlic : Stir in the minced garlic for 1 minute, just until fragrant—don’t let it brown.

4) Deglaze

• Pour in the white wine or vinegar and scrape up all the browned bits from the bottom of the pot.
• Let it simmer for 3–5 minutes, until the liquid is mostly absorbed.

5) Cook the potatoes

• Add the potatoes, broth, salt, pepper, rosemary, thyme, and bay leaf.
• Bring to a boil, then reduce to a gentle simmer for about 20 minutes, until the potatoes are very tender (a knife should slide in easily).

6) Blend and balance

• Remove the herb stems and bay leaf, then add the lemon juice.
• Blend with an immersion blender until smooth and velvety (or use a blender in batches).
• Taste and adjust salt, pepper, and lemon in small increments.

7) Serve

• Ladle into bowls, finish with a drizzle of extra-virgin olive oil and a sprinkle of fresh herbs.
• Serve immediately, piping hot.

Troubleshooting tips (texture, flavor, blending)

– How do I know the onions are ready? They should be soft, evenly deep golden-brown, and smell sweet and “jammy,” not sharp like raw onion.

– It’s burning or sticking : Lower the heat slightly, add 1 tbsp water/broth, scrape the bottom, and continue.

– Soup is too thick : Add water or broth gradually, blend for 10 seconds, then re-check.

– Soup is too thin : Simmer uncovered for 10 minutes, or blend in a small piece of cooked potato if you have one.

– It tastes a bit flat : Usually it needs salt or a touch more acidity. Add a pinch of salt, then a few drops of lemon, tasting each time.

– Blender safety : If using a countertop blender: blend in batches, don’t fill to the top, and vent steam to avoid splashes.

Storage and freezing

– Fridge (3-4 days): Cool fully, then store in an airtight container.

– Reheat: Warm gently on the stovetop, stirring; add a splash of water if it thickens.

– Freeze (2-3 months): Freeze in portions, leaving room for expansion. Thaw overnight in the fridge, reheat gently, and re-blend if the texture changes.

FAQ

– Can I keep the potato skins on? Yes, especially if they’re thin. Scrub well before chopping.

– White vinegar or balsamic? Both work: balsamic is smoother and slightly sweet; white vinegar is brighter and more sharp.

– Why add lemon at the end? It lifts the sweetness of the potatoes and richness of the broth, so the soup tastes cleaner and more vibrant.

– Do toppings really matter? Absolutely. A drizzle of olive oil (or a spoon of sour cream) adds contrast and makes the bowl far more interesting.

Other soups to try

• Cheesy French Onion Soup
• Creamy mushroom soup
• Carrot soup