Sift the plain flour and 1 tsp fine salt into a large bowl or the bowl of a stand mixer. Measure out 240-260ml lukewarm water into a jug. Make a well in the centre of the flour and add 2 tbsp olive oil, the vinegar and most of the water, reserving the rest.

If kneading by hand, bring the mixture together using a fork or your hands, adding the remaining water gradually until you have a soft, supple dough. Turn out onto a lightly floured surface and knead for 8-10 mins until smooth, elastic and springy. If using a stand mixer fitted with the dough hook, mix on low speed for 1-2 mins until combined, adding the remaining water if too dry or a light dusting of flour if too sticky. Turn up the speed to medium-high and knead for 5-6 mins until the dough is smooth and coming away from the sides of the bowl.

Lightly oil a clean bowl with 1/2 tsp olive oil. Put the dough in the bowl and lightly oil the surface using the remaining oil. Cover and leave to rest at room temperature for at least 2 hrs.

Once rested, divide the dough according to the shape of filo you want to make or the size and shape of tray you plan to use. For round sheets (to fit a round baking dish about 30cm in diameter), divide the dough into 12-14 equal-sized balls (about 50-55g each). For rectangular sheets (to fit a baking dish about 32 x 40cm), divide the dough into seven equal-sized balls (about 100g each).

Generously dust the work surface with the cornflour. Working with one dough ball at a time, roll the ball out from the centre outwards, turning frequently and dusting with more cornflour as needed. For round sheets, roll the balls out until they're 1-2mm thick and 30-35cm in diameter; for rectangular sheets, roll the balls out until they're 1-2mm thick and 32-35 x 40-45cm. When stretching large rectangular sheets, rotate the dough and lift it gently using the rolling pin, rather than dragging it – this will avoid sticking and tearing. Stack the rolled-out filo sheets between sheets of baking parchment, or dust generously with cornflour to prevent them from sticking together. Put a clean, damp tea towel on top to prevent them from drying out.

Immediately use the filo sheets in your chosen recipe or, to store, put a sheet of filo on a sheet of baking parchment and dust generously with cornflour. Stack the remaining sheets on top, dusting generously with cornflour between each layer. Cover with another sheet of baking parchment, fold it over loosely, then wrap and seal in a reusable food bag. Chill until needed, or for up to 48 hrs.