Eggs crash 5-6 minutes, gradually add the sugar. Add the melted butter and the beating continues. The flour is mixed with the baking powder, gradually add half of the egg mixture, stirring with a spatula. Once the meal is over, pour half of the chopped pineapple washers and ground walnuts. Again, stir and add the remaining half custard. Stir in one direction, until homogeneous, add the rest and pineapple chunks. Pour into greased and floured previously tray and bake 25-30 minutes in a preheated 160 C oven.