In a large pot, heat 2 tablespoons of olive oil over medium heat until shimmering, about 1–2 minutes. Add 1 chopped onion, 3 minced garlic cloves, 1 tablespoon of grated fresh ginger, and 1 teaspoon of turmeric powder. Sauté until the onion becomes translucent, approximately 5 minutes.

Add 2 diced potatoes, 1 cup of chopped cauliflower, 1 diced zucchini, 2 chopped carrots, and 1 chopped stalk of celery. Season with salt and pepper to taste. Stir well and allow the vegetables to sauté for another 5–7 minutes.

Stir in the juice of 1 lemon, then pour in 4 cups of vegetable broth and add a pinch of cayenne pepper. Bring the soup to a boil.

Reduce the heat to a low simmer and cover the pot. Cook for 10–15 minutes, or until the vegetables are tender.

Carefully transfer the soup to an immersion blender to puree until smooth, or use a traditional blender in batches. Return the blended soup back to the pot to heat through for a few minutes.

Taste and adjust the seasoning with more salt, pepper, or lemon juice as needed.

Ladle the creamy soup into bowls and top with Greek yogurt if desired. Serve hot.