Instructions

1. Preheat oven to 450°F. Place potatoes, 3/4 cup vinegar, and salt in a large pot. Cover with water by 1 inch. Bring to a boil, then reduce heat to a simmer for 15 minutes, until fork-tender. Drain and transfer to a rimmed baking sheet; let cool slightly.
2. Place another rimmed baking sheet on top and push down firmly to smash the potatoes. Toss potatoes with olive oil, onion powder, garlic, salt, and pepper. Roast until light golden brown, 25-30 minutes. Remove, sprinkle with cheese, toss, and return to the oven for 10 minutes, until crisp and golden.
3. Toss potatoes with the remaining 2 tablespoons vinegar, herbs, and chives.
4. Spoon yogurt onto a serving plate and arrange potatoes on top. Garnish with fresh herbs and flaky salt.