Preheat oven to 400°F. Line a sheet pan with parchment paper.
Toss potatoes with sesame oil, 1 teaspoon salt and wasabi powder. Arrange potato slices, in a single layer, on prepared sheet pan. Bake for 12 to 15 minutes, until golden brown. Set aside to cool.
Mash avocado, scallions, wasabi sauce, tomato, lime juice, and remaining 1 teaspoon salt to desired consistency. Taste and adjust seasoning.