1 sheet frozen puff pastry (preferably all butter), thawed, or sweet tart dough, chilled
1 stick butter, 120 grams (I use half)
3/4 cup sugar, about 100 g
about 8 sweet firm apples, such as Fudji, Gala or Golden Delicious, peeled, cored and quartered (I cut in halves)
Choose a 9 or 10 inches oven-proof skillet or a tarte Tatin pan.
Working on a floured surface, (if you are using puff pastry), or between wax paper or plastic wrap, roll the dough out until it sis about 1/8 inch thick (it can be thicker if you'd like). Using a paring knife, cut the dough into a circle that is 1 inch larger of the diameter of the pan you are using.
Prick the dough all over with the tins of a fork and refrigerate it while you work on the apples.
Put the skillet over medium heat and add the butter. When it melts, tilt the pan so that the sides have a thin coating of melted butter. Sprinkle the sugar over the butter. Remove from the heat.
What's important here is to pack in the apples-because they will shrink as they cook, you want to make sure they are snug in the pan. When you've got a tight single layer, cut the remaining apple halves (or quarters) in half and strew them over the first layer. (You might have to cut more apples to get a fairly even layer here, or you might have apple quarters left over).
Don't worry about making this layer beautiful -no one will see it, but it will give the finished tart a litte height.