• Mix flour, salt, and sugar in a large bowl. Cut the 6 tablespoons of butter cubes into the flour mixture, just until the butter is the size of large peas. Gradually add water, mixing gently. (The mixtures should be crumbly, but it should still hold together. If not, add more cold water, 1 tablespoon at a time.)
• Press the dough into a disk. Wrap in plastic wrap and refrigerate for 2 to 24 hours.
• Preheat the oven to 400°F. Heat4 tablespoons of butter in a skillet over medium-high heat.
• Add the onion and cook until golden brown. Add the potatoes and sauté for 5 minutes. Add 2 tablespoons of dill to the potato-onion mixture. Season with salt and black pepper, to taste.
• On a well-floured surface, roll the dough into a circle, 8 to 9 inches in diameter, and ⅛-inch thick. Place the dough in a shallow baking pan.
• Spoon the potato-onion mixture onto the center of the dough, leaving a 1 ½-inch border. Top with the gouda.
• Fold the border around the tart toward the center to encase part of the filling, crimping the edges as you go. Brush the folded-over edges with the milk or cream.
• Bake until the border is golden brown and the cheese is bubbly and golden brown, 25 to 30 minutes.
• Serve immediately with dollops of Crème Frâiche and 1 tablespoon of dill on top.

Giant Eagle Market District, marketdistrict.com.