In a large pot, pour in the chicken or vegetable broth and bring it to a gentle boil over medium-high heat. Cube your potatoes into uniform pieces and add them to the pot. Reduce the heat to medium-low and simmer for about 15 minutes until tender.

Heat a tablespoon of olive oil in a skillet over medium heat. Add diced onion and grated carrot, sautéing for about 10 minutes until the onion is translucent and the carrot softens.

Transfer the sautéed onion and carrot mixture into the pot with simmering potatoes. Add chopped zucchini and fresh spinach, cooking for an additional 5-7 minutes until tender.

Season the soup with salt and pepper to taste. Add lemon juice, stir in the cubed hard-boiled eggs, and garnish with parsley or dill.

Serve warm in bowls, topped with a dollop of sour cream, and enjoy this comforting dish.