Twice Cooked Boiled then Roasted Potatoes with Vegan Almond Tzatziki and Za'atar

Preheat oven to 450F. In a large pot, boil water and add potatoes. Cook until tender. Strain and let cool. Transfer potatoes to greased foiled baking sheet. Using back of a spoon or fork, press down on each potato 'smashing' it. Brush with oil and season with salt and pepper. Roast for 20 minutes until edges crisp up. While potatoes are roasting, mix tzatziki ingredients. Let potatoes cool and top with a dollop of tzatziki and a sprinkle of zaatar.