Peel and chop the potatoes into 2.5cm (1-inch) cubes, ensuring they’re roughly uniform for even cooking.
Heat the large pot over medium heat, then add the olive oil. Once shimmering, toss in the diced onion and sauté until translucent and fragrant, about 5 minutes. You’ll notice the onions soften and begin to turn a light golden color.
Add the chopped potatoes and minced garlic to the pot. Stir well to coat everything in the fragrant oil and cook for another 2 minutes until the garlic is aromatic and slightly golden.
Pour in the vegetable broth, ensuring the potatoes are fully submerged. Increase the heat and bring the mixture to a gentle boil. You’ll hear a steady bubbling as the broth heats up.
Once boiling, reduce the heat to low, cover the pot, and let it simmer gently for 20-25 minutes. The potatoes should become very tender and easily pierced with a fork, filling your kitchen with a warm, comforting aroma.
Remove the pot from heat and carefully use an immersion blender to blend the soup directly in the pot until smooth and velvety. If using a traditional blender, blend in batches, then return the pureed soup to the pot.
Stir in the plant milk and season with salt and pepper, tasting as you go. Warm the soup over low heat for another 5 minutes, allowing the flavors to meld and the texture to become creamy.
Adjust the seasoning, adding more salt or a squeeze of lemon juice for brightness if desired. Ladle the hot, smooth soup into bowls.
Finish by garnishing with chopped fresh herbs for a burst of color and freshness. Serve immediately, enjoying the comforting aroma and creamy texture.