Beat the eggs with the sugar until white and add the butter. Sift the flour with the baking powder and salt and start adding it gradually, stirring gently with a spatula.
Then add the walnuts and half the chopped pieces of pineapple. Drain the raisins and add them too. Pour out the mixture into a greased tray, arrange the remaining pineapple rings on top.
Cover the tray with baking paper and place the cake with pineapple to bake in a pre-heated 356°F (180 °C) oven. Optionally, serve with powdered sugar.