Separate the eggs. Preheat the oven to 180°C. Sift the flour.
Draw two 8 x 27 cm rectangles onto a sheet of parchment paper. Draw lines in 3 cm increments. For the sides, see Hint 1.
Draw two 13 cm diameter circles on another sheet of parchment paper. This is for the bottom and the cookie sandwiched in the middle.
Put the egg whites in a bowl. Add the sugar in 3 batches while beating the egg white to make a stiff meringue (it should form stiff peaks).
Add the egg yolks one by one, mixing them in well.
Add cake flour and fold it in using a rubber spatula. It can still be a bit floury. Please be sure not to over mix.
Fit a 1 cm diameter circular tip onto a piping bag, and put in the batter. Flip the lined parchment paper and lay on a baking sheet.
Pipe the batter onto the paper following the guidelines. If you leave a little space in between each line, it will be very nice looking when done.
When the batter is all piped out, dust evenly with powdered sugar using a tea strainer. Leave for 1 minute and then dust with sugar again. Bake for about 10 minutes.
When the pieces are golden brown, cool on a rack, paper and all. When the fingers are cool, take the paper off.
Bake the circular base the same way. Form the circles in spirals starting from the center. Do it in one go without stopping.
Dust powdered sugar as with the side pieces, and bake for about 10 minutes in a 180°C oven.
Cut 5 mm off the perimeters of the circular base, and 1 cm off one edge of the rectangular pieces.
Line the sides of the cake mold with the side pieces with the browned sides facing out. Cut off excess crust. Line the bottom with one of the circular pieces with the browned side facing down.
Story Behind this Recipe
I made my favorite ladyfinger biscuits for a charlotte.
The grid is drawn as a guide to piping the ladyfingers. Make sure to pipe them with space in between, so that they don't get stuck to each other while baking. Ideally you want to bake the circular bottom and the side biscuits at once, but if that's not possible do it in 2 batches, starting with the sides.