Peel the nectarines and cut into slices. Toss with the lemon juice and a few pinches of sugar if the fruit is not too sweet. If the fruit is sweet and fresh skip the sugar. Set aside.
Cream the sugar and butter in a bowl until light and fluffy. Add the flour, baking powder, salt, and eggs and beat until combined.
Spoon batter into a 10 inch pie pan (it will look like there is not enough batter but there is). Place the nectarine slices on top of the batter packing them in tightly. Sprinkle lightly with lemon juice and some sugar, depending on the sweetness of the fruit.
Bake 50 to 60 minutes until golden brown. Cool. Refrigerate if desired. Sprinkle a bit of powdered sugar on top if desired.