01 - Heat olive oil in a large saucepan over medium heat. Add chopped onion and cook for 3-4 minutes until softened and translucent.
02 - Stir in minced garlic, sliced carrots, and diced potato. Cook for another 5 minutes, stirring occasionally to coat with aromatics.
03 - Sprinkle ground coriander over vegetables and cook for 1 minute until fragrant, stirring constantly to prevent burning.
04 - Pour in vegetable stock and bring to a boil. Reduce heat to low and simmer for 20 minutes until vegetables are very tender and easily pierced with a fork.
05 - Remove from heat. Use a stick blender or transfer to a countertop blender to purée until completely smooth and velvety.
06 - Stir in double cream and most of chopped fresh coriander. Season generously with salt and pepper to taste. Keep warm.
07 - Preheat grill or broiler to high setting.
08 - Butter bread slices generously on one side and sprinkle with grated Parmesan cheese.
09 - Place bread on baking tray and grill for 2-3 minutes until cheese is melted, golden, and bubbling.
10 - Ladle hot soup into bowls, garnish with reserved coriander leaves, and serve with Parmesan toasts on the side.