Add butter in a large pot over medium heat.

Dice the onion and slice the white to the pale green part of the leek and discard of the green part of the leek.

Add the onion, leeks, celery salt, black pepper and minced garlic in the pot and cook until softened. Please stir often.

Add the diced potatoes and stock. Cook until the potatoes start to fall apart.

Turn off the heat. Remove a couple of spoonfuls of the potato and leek mixture and place in a bowl.

Blitz the remaining mixture using a stick blender.

Turn the stove back on medium heat and add in the thicken cream. Cook until the soup is nice and hot.

Pour a generous amount of the soup mixture into a bowl. Top each bowl with the left over potatoes and leeks.

Drizzle over a little of the heavy cream, olive oil, black pepper and some chopped parsley. Serve with some crispy bread.