Feed your mature starter and leave it for 4-6 hours until it doubles in size, becomes bubbly, and passes the float test.

In a large bowl, measure 100g of starter and save the rest in the fridge. Add water and honey, mixing well.

Add the flour and salt, then mix thoroughly using a dough whisk or your hands. Cover the bowl with a clean towel and let it rest for 30 minutes.

Take a section of the dough from the bottom and stretch it upwards. Fold it over the remaining dough. Rotate the bowl and repeat until the entire dough is stretched.

Drizzle olive oil in a bowl or Pyrex dish. Transfer the dough into the bowl and coat it with more olive oil.

Cover the bowl and let the dough rise at room temperature for 4-18 hours until it doubles in size. The rise time depends on your kitchen temperature and starter strength.

Line a 9×13-inch pan with a reusable liner and drizzle with oil. Gently release the dough from the bowl and place it in the prepared pan.

Fold the dough in half by scooping from the middle, then fold it into thirds (like an envelope) to form a rectangle. Turn it seam-side down.

Cover the pan with a large plastic bag and let it rise at room temperature until nearly doubled, spreading out to fill most of the pan (4-6 hours).

Preheat the oven to 425°F. Dip your fingers in olive oil and press deeply into the dough to create dimples. Sprinkle generously with coarse sea salt.

Bake for 25 minutes until the focaccia top is golden. Using the liner, lift the bread onto a cooling rack and let it cool for 30 minutes before slicing.