Preheat the oven at 350 Deg F.
Whip the eggs with the sugar for about 5 minutes
Add flour and vanilla and beat at reduced speed for 2-3 minutes
Add the baking powder and beat in for a minute.
Mix in the apples manually.
Butter a baking pan 9" dia, with a removeable bottom and fill with the mix.
Bake in the center of the oven for about 45 minutes.
Serve warm, possibly, or at room temperature.