Directions

1.Pastry: In a bowl, combine the flour and salt. Cut up the butter into 1/2in chunks and cut into flour using pastry blender or two knives, until mixture resembles coarse meal. In a small bowl, whisk together the sour cream, lemon juice and water and add this mixture to the flour mixture. With a fork, mix in liquid carefully until large lumps form. Do not overwork the dough. Place dough in plastic wrap and lightly and briefly knead with knuckles and until dough mostly sticks together, without lots of dry parts (like 30 seconds). Wrap tightly in the plastic and refrigerate for 1 hour.

1. Prepare squash: Preheat oven to 375F (190C). Peel squash, then halve and scoop out seeds. Cut into a 1/2-inch dice. Toss pieces with olive oil and a half-teaspoon of the salt and roast on foil lined sheet for 30 minutes or until pieces are tender, turning it midway if your oven bakes unevenly. Set aside to cool slightly.

2. Caramelize onions: While squash is roasting, melt butter in a heavy skillet and cook onion over low heat with the remaining half-teaspoon of salt and pinch of sugar, stirring occasionally, until soft and lightly golden brown, about 20 minutes. Stir in cayenne.

3. Raise the oven temperature to 400F (205C). Mix squash, caramelized onions, cheese and herbs together in a bowl.

4. Assemble galette: On a floured work surface, roll the dough out into a 12-inch round. Transfer to an ungreased baking sheet. Spread squash, onions, cheese and herb mixture over the dough, leaving a 1 1/2-inch border. Fold the border over the squash, onion and cheese mixture, pleating the edge to make it fit. The center will be open.

5. Bake until golden brown, 30 to 40 minutes. Remove from the oven, let stand for 5 minutes, then slide the galette onto a serving plate. Cut into wedges and serve hot, warm or at room temperature. Serves 6.