Very sticky dough – Put the flour, yeast and salt in a bowl, mix to combine with a rubber spatula. Make a well in the centre, pour the warm water in then mix until you no longer see flour. It should be like a thick muffin batter – way too sticky and loose to knead.
Rise #1 (2 hrs) – Cover with cling wrap then put in a very warm place to rise for 2 hours or until doubled in volume, or do Rise #1 in the fridge 24–48 hrs.
Line pan – Use a 26.5 x 20 x 5cm (10.5 x 8 x 2") rectangle pan (metal, not glass or ceramic) or a 22cm/9" square pan. Lightly grease with butter (not oil). Scrunch up a sheet of baking paper, un-scrunch then press into the pan, ensuring you have overhang to lift the focaccia out later.
Dough in pan – Drizzle and spread ½ tablespoon of olive oil in the pan on the paper. Pour the dough batter in, then use 2 rubber spatulas to coax the dough out into the corners as best you can. Don't get too hung up on this, it will fill the pan as it rises.
Rise #2 (45 min) – Cover with a cutting board (or similar flat item, but make sure there's enough space for the dough to rise), then put in a very warm place for 45 minutes or until it rises by 50–70%. You should see some nice big bubbles on the surface. Halfway through, preheat oven.
Preheat the oven to 220°C / 425°F (200°C fan-forced) with the oven rack in the middle.
Drizzle 1 tbsp of olive oil across the surface. Rub a little oil on your fingertips then use your fingers to spread the oil lightly across the surface.
Light dimpling – Use your fingers to lightly press dimples into the surface of the dough, only pressing down about 1cm/0.4" into the dough, not all the way down like traditional focaccia else you will deflate the dough.
Sprinkle salt flakes all over the surface.
Bake for 25 minutes, rotating the pan at the 15 minute mark, until the surface is deep golden.
Cool 10 minutes – Lift the focaccia out of the pan using the excess paper onto a cooling rack, then slide the paper out from underneath. Cool for 10 minutes before serving. Always best served warm.
Serve cut into 4cm/1.5" wide strips then each into 2 pieces. Great as an appetiser or for nibbling with drinks. Makes excellent cheese toasties and sandwiches. Serve with extra virgin olive oil for dipping, optionally with a swirl of aged balsamic vinegar.