This is a lovely, moist sponge that I’ve used in entremets (layered mousse cakes) and Swedish vacuum cleaner cakes (dammsugare).

Preparation

• Line medium-sized baking tray with baking paper – around 30cm x 22cm (12in x 8.5in) wide for a sponge around 1.5cm/1/2 inch high.
• Preheat oven to 160°C/320°F (fan/convection oven) or 180°C/350°F (static).

Ingredients

• 35g/1/3 cup less 1 tsp ground almonds
• 40g/1/3 cup gluten-free flour (I used Doves Farm self-raising gf flour) or standard cake flour (1/3 cup + 3 and 1/3 tsp)
• pinch fine sea salt (1/8 tsp)
• 65g/1/4 cup + 2 tsp caster/superfine sugar (I used golden unrefined)
• 55-60g egg yolks (about 3 yolks from medium/large free-range eggs)
• finely-grated zest from 1 orange or lemon
• 1/2 – 1 tablespoon freshly-squeezed orange or lemon juice (maybe 1/2 tbsp with standard cake flour)
  
• 25g/1 tbsp + 2 and 1/3 tsp caster/superfine sugar (preferably golden unrefined)
• 145g/ml egg whites (about 3 and 1/2 whites from medium/large eggs)

Optional spices to add at Step 4:  1/2 tsp each of pure vanilla extract, ground cinnamon, ground ginger (or 3/4 tsp for stronger flavour).

Method

1. Whisk to combine dry ingredients (flour, almonds, salt) in small bowl.
2. Separate eggs into 2 big bowls (make sure whites have no traces of yolk and are in very clean bowl).
3. Whisk yolks and sugar with zest until pale and fluffy.
4. Whisk in juice and optional spices.
5. In other bowl, with a clean whisk, whisk whites to soft peak.
6. Gradually whisk sugar into whites to get shiny stiff peaks that don’t fall out of bowl when turned upside down.
7. Gently fold in 1/3 flour and 1/3 stiff whites into yolk mixture.
8. Repeat step 7 with second 1/3 of flour and whites, then when almost combined with the last thirds.  Don’t overmix or it flattens out.  Be gentle and as brief as possible.
9. Pour into prepared tray lined with baking paper.
10. Smooth with offset pallet knife and minimum number of movements.
11. Bake in middle of oven 8-12 mins until inserted skewer comes out clean and top springs back slightly when pressed lightly with finger tip.
12. Once baked, immediately turn out onto wire rack to cool completely before assembling cake.

Storing

If storing, keep 1-2 days loosely wrapped in plastic bag at room temperature or in freezer (freeze on tray first then wrap tightly in plastic film).  Sponge can be inserted frozen in cake.

Here’s the cakes made with it so far…

and in the filling…