Put the starter into a large bowl. Add water, honey and 60ml of olive oil. Stir well
Add the flour and salt and use a large fork to mix into a sticky dough
Cover the dough and allow it to rest for 30 minutes
Wet your hands and stretch and fold the dough 4 times, turning the bowl 90 degrees for each stretch and fold
Then cover and rest for a further 30 minutes before repeating the stretch and fold. If possible do this four times in total.
Cover the dough and place in the fridge overnight. In the morning, remove from the fridge and allow to rise for a further 2 hours
Cover a large baking tray with a silicon liner, then pour in 30 ml of the oil
Turn the dough out onto it and fold into a rectangle
Flip the rectangle over and use the palms of your hands to gently push the dough out as far as possible till it is no more than 1cm deep
Cover and allow to rise in a warm place till it has doubled in size
Pre-heat your oven to 220c
Now very gently use your finger tips to make dimples in the dough, pressing right through to almost the base of the tray
Make up your salamoia by whisking together 30ml of oil, 30 ml of water and 5 g of sea salt
Use a pastry brush to liberally baste the dough. You can allow the salamoia to fill the dimples of the focaccia, it will help keep the dough light and soft
Scatter the rosemary into the dimples of the dough
Bake for 20-25 minutes till the focaccia is golden brown
If you like, you can baste the still warm focaccia with more oil
Allow to cool for 10 minutes before serving warm