- Preheat your oven to 180 C / 160 C Fan / Gas 4. Get a 23cm (9 in) springform tin ready: oil the inside of the ring and the bottom of your tin, and line the bottom with baking paper, ensuring the paper covers the join of the ring. Very lightly oil the top of the paper as well.
- Whisk the olive oil and sugar on medium speed in a large bowl until very light and creamy. Add the eggs one at a time, whisking continuously. Add the rosemary, orange zest and juice, and continue whisking until fully combined and frothy. (You can use an electric hand-held or stand mixer for this, or an immersion [stick] blender works fine too.)
- In a small bowl, manually stir the flour, baking powder and cinnamon together with a fork. Briskly stir the dry ingredients into the wet (remember, this is gluten free so you don't have to worry about over-mixing; keep as much incorporated air as you can). Your cake mixture will be thin, more like pancake batter than cake. Pour the mixture into your prepared tin.
- Bake for 40 to 45 minutes, turning the tin halfway through for even baking, until the centre bounces back springily when lightly touched with your finger.
- Cool the cake in the tin on a cooling rack for about 10 minutes. Run a spatula or palette knife around the ring to loosen, then un-clip and lift off the ring, and leave the cake to cool completely on the tin's base.
- When the cake has baked, turn the oven off. Spread the remaining orange zest on an oven-safe plate, breaking up any clumps, and place in the oven (door ajar) to dry out as the oven cools.
- Stir the icing sugar and 2 to 3 tablespoons of the orange juice together until fully combined. (See footnote.)
- Turn out the fully cooled cake onto a serving plate/platter. Pour the glaze over the cake, sprinkle over the dried orange zest, and grate some fresh nutmeg over. Sprinkle over the chopped rosemary.
Dried herbs v fresh?
I tested this recipe using dried rosemary, and I don't recommend it. The pine-y aroma of fresh rosemary is really required for the cake to taste as stupendous as it should. Also, dried rosemary doesn't bake into the cake properly and is too spiky for the topping. Chop the fresh rosemary as finely as you can, though, as larger bits aren't nice to bite into.
For the photographed cake, I used 4 small oranges (2 for the cake, 2 for the glaze), weighing between 175g and 195g each. For a thicker glaze, use only 2 to 3 tablespoons of the orange juice (mine was more like lemon drizzle, which is what I wanted). There is enough glaze to spoon some over each served cake slice as well.
See it on my blog