Step 1

Put the olive oil in a frying pan over moderate heat.Add the chopped onion, garlic and dried chillies plus a little salt and pepper.Fry until the onion is soft and golden, stirring often. If necessary, turn down the heat to stop it burning (12-15 min).Take the pan off the heat and leave to cool a little.

Step 2

Put the flour, 1 tsp of salt, plus the onion/nigella seeds if using, into a large bowl.Stir in the contents of the frying pan, including any oil.

Step 3

Using instant yeast:Sprinkle the yeast into the flour mixture and stir in.Pour in the 220ml of water.Using sourdough starter:Dissolve the starter in the 180ml of water.Pour the mixture into the bowl containing the flour etc.

Step 4

Stir to make a wet dough, making sure everything is well combined.Note: different flours absorb different amounts of water. Add more water if the dough seems dry.Cover the bowl and leave overnight or 12-16 hours.

Step 5

The dough, still quite wet, should be well risen and very bubbly. Leave a little longer if necessary.

Step 6

Scrape the dough out of its bowl and onto a worktop well dusted with flour.

Step 7

Fold the dough several times, dusting with flour to prevent sticking, until it comes together into a smooth ball.Flatten out the dough a little then sprinkle over 75g of the grated cheese.Fold it in half to cover the cheese, then keep folding until the cheese is distributed throughout the dough. Add more flour if needed to stop it sticking.Shape the dough to fit a floured proving basket or a bowl lined with a floured tea towel and put it inside.

Step 8

Cover the dough and leave until the depression left by a finger pressed into the dough slowly rather than quickly springs back. If it springs back immediately then leave to prove for longer.Note: proving will take approximately 30 minutes for dough made with instant yeast and 60-90 minutes for sourdough. However, this will vary depending on, among other things, the temperature in your kitchen. It's best to test as above before baking.

Step 9

While the dough is proving: preheat the oven to its highest setting and put inside a cast iron pot or Dutch oven, including its lid.

Step 10

When ready to bake, remove the pot from the oven and take off the lid.Carefully flip the dough from its basket or bowl into the pot.Sprinkle the top with the remaining 25g of grated cheese.Slash the top, replace the lid and put in the oven.Immediately turn the heat down to 240C /220 Fan /Gas 9.Bake for 30 minutes without removing the lid.

Step 11

After 30 minutes, reduce the heat to 220C /200 Fan /Gas 7.Remove the pot from the oven, tip the bread out of it, then return the loaf to sit directly on the oven shelf.Bake for a further 8-15 minutes until the bread is cooked through (it should sound hollow when tapped underneath).If necessary, reduce the oven temperature to stop the crust over browning before the bread is finished baking.

Step 12

Place on a wire rack to cool before eating.Use within 2-3 days, or can be frozen once completely cold.