Prepare your leeks by slicing them. Peel the potatoes and cut them in cubes.
Choose a bigger pot so you can fit all the ingredients in it but also gives you enough space to blend. Place the pot on medium heat and add the leeks. Let them cook for 2-3 minutes. Add the potatoes, vegetables broth, salt and pepper.
Let it boil on a medium heat until the potatoes are tender. Remove some of the broth if you want your soup on the purée side. Add the cream and let it boil for 2 more minutes.
Remove the pot from the heat, let it cool for 5 minutes and then blend it using a immersion blender. You can now add more salt and pepper if you need to. Blend it until there are no lumps and it has a creamy texture. Serve it with crispy onions, croutons, extra cream or...all of them!