Baking with olive oil
Olive Oil Orange Cake: A Recipe for a Moist Crumb
One specific cake, not the general butter-to-oil conversion: how much extra virgin olive oil goes into the batter, how the zest and juice carry the orange flavour, and why the crumb stays moist for days without the fridge.
The short answer
This is one cake, not the general baking substitution: 180 ml extra virgin olive oil, orange zest rubbed into the sugar, juice in the batter, baked plain and finished with a citrus glaze or a dusting of icing sugar. The oil is what keeps the crumb moist at room temperature for days.
This cake is built around one fat from the start rather than a butter recipe adjusted afterward, and it holds together differently because of it: a close, moist crumb under an orange glaze, no dairy in the batter, and no fridge needed once it cools.
This is one specific recipe, not the general olive-oil-for-butter ratio — for that conversion see olive oil for cakes and baking. Here: how much oil, how the zest and juice go in, the method, and how to finish it.
Why Oil, Not Butter, for This Cake
Butter is roughly a fifth water, which bakes off in the oven and leaves the crumb to dry out over a day or two. Extra virgin olive oil is entirely fat, so it keeps coating the crumb after baking instead of evaporating out of it.
That is a fact about this particular batter, not a general rule for swapping the two fats in any cake — the conversion ratio between butter and oil for baking more broadly is covered at olive oil for cakes and baking, not repeated here.
How Much Oil Goes Into the Batter
For one 20 cm round cake: 180 ml extra virgin olive oil, 3 eggs, 220 g caster sugar, 240 g plain flour, 2 teaspoons baking powder, a pinch of salt, the zest of two oranges and 120 ml fresh orange juice.
A mild extra virgin oil suits this cake better than a peppery one — the sharper the pepper note, the more it fights the orange rather than sitting underneath it. Any of this site's plain 250 ml or 500 ml bottles works; see the products page for sizes.
Building the Orange Flavour: Zest and Juice
Rub the orange zest into the caster sugar with your fingertips before anything else goes in the bowl — the sugar's abrasion pulls the citrus oils out of the zest, and the mixture turns damp and fragrant within a minute.
The juice replaces part of the batter's liquid rather than sitting on top as a flavouring, so it needs to go in with the eggs and oil, not stirred in at the end. Squeeze it fresh; bottled juice tastes flatter and thinner in the finished crumb.
Method: Mixing and Baking the Cake
This batter comes together in one bowl with a whisk, no electric mixer needed, and bakes at 170°C for about 45 minutes. Test it the ordinary way: a skewer through the centre should come out clean, not wet.
- Rub the orange zest into the sugar until damp and fragrant.
- Whisk in the eggs, oil and orange juice until smooth.
- Fold in the flour, baking powder and salt just until no dry streaks remain.
- Pour into a greased, lined 20 cm round tin.
- Bake at 170°C for 40–45 minutes until a skewer comes out clean.
- Cool in the tin for 10 minutes, then turn out onto a rack.
A Simple Glaze or Icing Sugar Dusting to Finish
A thin glaze of icing sugar loosened with fresh orange juice, spooned over the cake once it has fully cooled, sinks slightly into the top and sets into a matte, faintly sticky finish rather than a hard shell.
For a plainer finish, skip the glaze and sift icing sugar over the top just before serving — it suits a cake meant to be cut again the next day, since a glaze left on for two days turns tacky while a dusting can simply be reapplied.
Why It Stays Moist for Days Without the Fridge
Kept under a cake dome or wrapped at room temperature, this cake is still moist on day three or four, because the oil that coats the crumb does not evaporate the way butter's water content does, and does not stiffen the way chilled butter does in the fridge.
Refrigerating it is unnecessary and works against the texture: a cold, oil-based crumb turns denser and loses the softness it has at room temperature, so it is worth cutting only what will be eaten within a few days rather than storing the rest cold.
The Short Version
180 ml extra virgin olive oil, zest rubbed into the sugar, fresh juice in the batter, baked plain at 170°C, then finished with a citrus glaze or a dusting of icing sugar. Kept at room temperature, it stays moist for days — no fridge, no butter.