Beat the butter with the sugar, salt, zest and oil until it has gone lighter in colour. You can do it using an electric mixer with the whisk attachment or with a metal hand whisk.
Add the eggs and beat the mix again until incorporated and airy.
Add the honey and mix again. Then do the same with the milk and juice.
Add the flour and baking powder and mix.
Prepare a 22x11cm mould with baking paper. Cut the paper to size and stick it in place using a bit of vegetable oil.
Fill the mould with the mix and level it.