Beat eggs with a pinch of salt until foamy. Start adding sugar a few tablespoons at a time. Add next portion once previous sugar has been dissolved.
Continue beating egg and sugar mix for 10 more minutes (should take around 15 minutes total). Stand mixer will be really handy.
Mix corn starch with flour.Start sifting in corn starch and flour mix into the beaten eggs. Fold it gently moving your spatula from the bottom to the top. Once first portion of flour mix is incorporated, add in another portion. Continue until you have used all the mix.As a result you should get very light and airy batter.
Pour in the sponge cake batter into the pan. Level with a spatula if needed.
Bake in a preheated to 320F oven for 40-50 minutes.
Do a toothpick test at 40 minute mark. If toothpick come out dry (not sticky and without any crumbs stuck to it) sponge cake is ready. Otherwise leave for another 5-10 minutes. Of course, look for nice light golden brown color as well.
Take the pan out of the oven and let the cake cool before taking it out. Dust with powdered sugar and serve or use further in the other recipe.
This quantity of ingredients is enough for 9-10 inch cake pan. You can even get away with a large pan but sponge cake will be thinner. Perfect if you just need one layer or going to enjoy it plain.
Italian Sponge Cake https://www.italianrecipebook.com/sponge-cake/