To make the tart pastry, whisk together the flour and granulated sugar. Cut in the cold butter (I like to grate the butter in with a cheese grater and then combine it with my fingers until coarse crumbles form). In a small bowl beat together the egg yolks and ice water. Gradually stir the egg mixture into the flour and then gently knead until a ball forms. Don't overwork the dough. Wrap in plastic and refrigerate for at least 30 minutes and up to an hour.
Preheat the oven to 450°F. Lightly flour a work surface and press or roll out your tart pastry to the same shape as your pan, just larger. ***See Notes*** Press the crust into the pan. Cover the crust with parchment paper and then pour dried beans (or pie weights!) over the parchment. Bake for 8 minutes. Remove the weight from the top of the crust and bake for 4 more minutes. Set the crust aside to cool and reduce the oven temperature to 400°F.
In a large skillet over medium high heat, melt the butter. Stir in the brown sugar, salt, and nutmeg. Then add the squash. Cook for about 5 minutes stirring frequently.
Carefully remove the squash from the pan and layer it in the prepared crust. ***See Notes***
Spoon the remaining liquid over the squash (you may not need all the liquid -- my squash was a little watery and I didn't need all of it) and then sprinkle with the coarse sugar.
Bake uncovered for 15 minutes. Sprinkle the cheese over the tart and then bake for 5 more minutes.
Serve slices topped with whipped cream and sprinkles of ground nutmeg. ***See Note***
Notes
1. I used a 9" round tart pan with a removable bottom. The original recipe calls for an 11 X 8 tart pan with a removable bottom. With either I'd recommend cutting a piece of parchment just slightly larger than the bottom of the pan to line the pan with before pressing the crust in. When you press the crust into the pan, keep the thickness even across the bottom and sides (this will help the crust stay together when you remove the tart from the pan). 2. If you do not have parchment paper, dried beans, and/or pie weights, you can line the tart crust with a double layer of foil before baking. 3. If you are using a round pan, layer the squash like you would apples for a pie. If you are using a rectangular pan, the slices will be spread farther apart, overlapping just slightly. 4. You can serve this with sweetened whipped cream or you can make homemade unsweetened whipped cream. If you go that route you may want to add the ground nutmeg to the whipped cream with a little orange zest.