Beat the eggs and sugar with a mixer to obtain a fluffy cream. Then add the flour, baking powder and pinch of salt. Beat until you get a homogeneous mixture. Pour the mixture into a baking dish and bake at 374°F (190 °C) for about 30 min.
Check to see if it's baked with a long, narrow wooden skewer. Poke the sponge cake with it in several spots. If there's no raw dough stuck to it, it means it's ready.
Prepare the syrup from the listed ingredients, by bringing them to a boil in a pot on the stove and boiling for 10 min. or so.
Cut the sponge cake into squares or rectangles and pour the syrup over it.
You can pour warm syrup over the cold sponge cake or vice versa. Optionally, you can add some kind of essence to the syrup.