Fill a large saucepan with water and add a dash of salt. Place the pan over high heat until boiling. Then add the garlic and potatoes.
Turn the heat lower and cook the potatoes for about 20 minutes. In the meantime peel and trim the carrots. Slice them up. Add half of the sliced carrots to a medium saucepan and add the milk. Season it with pepper, nutmeg and salt.
Bring the carrots and milk to a gentle simmer and cook for about 8 minutes until soft.
Remove the cooked carrots (keep the milk aside for later) using a slotted spoon and add them to a blender. Also add the grated ginger and a pinch of pepper, nutmeg and salt.
Blend into a fine puree.
Add the remaining sliced carrots to the boiling potatoes 5 minutes before the end of cooking time.
Then drain the cooked carrots and potatoes. Transfer them to the same pan again. Add the butter and season with a little pinch of pepper, nutmeg and salt.
Mash them up a little. Then add the blended carrot and ginger puree and a splash of the warm carrot milk you kept aside earlier on.
Stir the carrot mash well. Add more milk if you like. Then check the seasoning and add extra pepper, salt, nutmeg or butter if necessary. Scoop the carrot mash onto warm plates and serve hot.