Place prepared potatoes in a large pot of cold salted water. Bring to a boil and cook until tender, about 20 minutes. Drain and return to pot.

Add butter and let melt. Add milk and mash.

Add wasabi powder and generously salt the potatoes. Mash them with a potato masher. If you prefer a smooth consistency, you may then puree with an immersion blender or hand blender.

Stir in Greek yogurt. Garnish with wasabi peas.