Why This Formula Works

The recipe uses 175 g of ground almonds to give the eggs enough structure to support the cake as it cools. The orange juice is measured rather than taken from an entire orange, because the amount of juice can vary widely. Too much free liquid can leave the center weak, especially when the eggs have been whipped to a very airy ribbon stage.

The eggs, sugar, zest, and juice are whisked together only until pale and slightly thickened. The almond mixture is then folded in gently. This gives the cake some lift without making it dependent on a fragile foam. A small amount of baking powder supports the rise without creating an overly tall dome that can collapse.

Ingredient Notes

• Use room-temperature eggs so they combine smoothly with the sugar.
• Zest the orange before squeezing it. The colored outer peel contains the aromatic oils; avoid grating deeply into the bitter white pith.
• Measure the juice in a jug or measuring spoon. Do not substitute the juice of a whole orange without checking the volume.
• Almond flour and finely ground almonds both work. A very coarse meal will give the cake a more textured crumb.
• The sliced almonds and icing sugar are optional. Greek yogurt or a sharp fruit coulis balances the sweetness when serving.

How to Make It

Whisk the eggs, sugar, orange zest, and orange juice together for 2 to 3 minutes. The mixture should look paler and a little thicker, but it does not need to reach a stiff ribbon stage. Separately combine the ground almonds, baking powder, and salt, then fold them into the wet mixture in two or three additions.

Spread the batter in a parchment-lined 20 cm tin. Bake at 170°C conventional or 160°C fan for about 30 to 38 minutes. The center should be set and spring back lightly. If the top is coloring quickly, cover it loosely with foil rather than increasing or extending the heat. Let the cake cool in the tin for 15 minutes before moving it to a rack; the crumb becomes firmer as it cools.

Troubleshooting a Sunken Center

If the cake domes and then drops, the center was probably still too fluid to support the risen edges. Common causes are too much orange juice, aggressive mixing after the eggs were aerated, or removing the cake before the center had set. Use the specified 45 ml of juice, fold only until combined, and check the center rather than relying on the edges or the dome.

A 20 cm cake made with this quantity may be ready well before the original 55-minute estimate, especially if the batter is shallow or the oven runs hot. Start checking around 28 to 30 minutes, but remove it only when the center is lightly springy. A clean knife is not the only useful cue for an almond cake because the finished crumb remains moist.

Serving, Portions, and Storage

Cut the cake into 8 slices. One slice makes a practical dessert portion, particularly when served with Greek yogurt or fruit rather than several sweet toppings. It is suitable as an after-dinner treat or with tea or coffee. If having it on a day with other rich foods, keep the rest of the day's snacks lower in saturated fat.

Store the cooled cake in an airtight container for up to 3 days at room temperature or up to 5 days in the refrigerator. For longer storage, freeze the undecorated cake, well wrapped, for up to 3 months. Thaw it overnight in the refrigerator and bring it to room temperature before serving.

Frequently Asked Questions

Is this cake gluten-free?

It is made without wheat flour, using ground almonds instead. Check the labels on the almond flour and baking powder if you need to avoid gluten because facility handling varies by brand.

Can I reduce the sugar?

A small reduction is possible, but sugar contributes to moisture and helps stabilize the egg mixture. Reducing it by more than about 15 to 20 percent may make the cake drier and less tender.

Can I use another nut meal?

Finely ground hazelnuts can replace some or all of the almonds, although the flavor will be stronger and the texture may be slightly more delicate. Avoid coarse chopped nuts in the batter because they do not provide the same structure.