Preheat oven to 350 degrees Fahrenheit.
Grease and line two-inch, round cake pans.
Combine flour, baking powder, and salt in a mixing bowl and set aside.
Beat butter and sugar in a large bowl until light and fluffy, about 5 minutes. Add the eggs 1 at a time, beating after each is added. Add the flour mixture and beat at the lowest speed possible until smooth.
Pour the batter in the cake pans evenly then bake for between 18 and 22 minutes until the outer edges are golden brown and the center is still pale. Test with a toothpick. If it comes out clean, it's done.
Cool on wire racks for 10 minutes. Then place 1 cake on a tray, round metal pan, cardboard, or a plate. Spread the jam on the cake evenly to the perimeter. Then place the second cake on top.
Dust with confectioner's sugar. Serve with whipped cream and fresh berries to complete.