Peel potato(es) and carrot and cut into very small pieces.
Chop onion, mince garlic.
Rinse very well celery stalks (with leaves) and cut into small pieces.
Bring a saucepan over high heat and pour the olive oil.
When the olive oil is hot add nutmeg and cumin, stir for abut 20 seconds and add onion, garlic, potatoes, carrot and celery, stir for 1-2’ then add tomatoes, tomato paste and sugar.
Add 3-4 cups water.
Reduce the heat to low and cook for 20’.
Add salt and pepper and oregano.
Cook for 5’.
Let the soup cool and puree it (for better result use hand blender).
Serve the soup with croutons and a spoonful greek yogurt per serve.
To make croutons: cut some bread slices into small cubes. Line a bake sheet with a parchment paper, layer the bread cubes, drizzle on olive oil drops and bake for about 5’-8' to 360º F or 180º C.