Preheat oven to 170°C (static heat). Line the base of a 20 cm round cake pan with baking paper, but do not grease the sides.

In a large bowl, beat the eggs, sugar, vanilla, and salt with an electric mixer on medium-high speed for 8–10 minutes until very pale, thick, and tripled in volume. The mixture should fall in ribbons when lifted.

Sift the flour over the egg mixture in two additions and gently fold it in with a spatula, using slow upward motions to avoid deflating the batter.

Pour the batter into the prepared pan and smooth the top gently. Bake for 25–30 minutes until golden and the center springs back when lightly pressed.

Remove from the oven and let the sponge cool completely in the pan for 10 minutes, then run a knife around the edge and turn it out onto a wire rack to cool fully before slicing.

Drain ricotta overnight and pass through a fine sieve until smooth and creamy.

Mix ricotta with 180 g sugar until fully smooth, then fold in chocolate chips, candied fruit, and orange zest.

Slice the cooled sponge into 1 cm layers and cut to fit a 20 cm springform pan. Roll marzipan to 3–4 mm thickness and line the sides of the pan evenly.

Place sponge base in pan, brush lightly with simple syrup, spread ricotta filling evenly, top with final sponge layer, press gently to compact, refrigerate covered for at least 8 hours or overnight, then unmold, glaze with powdered sugar icing (100 g sugar mixed with 2–3 tbsp water), decorate with candied fruit, chill 1 hour, and slice with a warm knife.