Combine the starter ingredients in a bowl. Mix well. Tip it into a clean jar. Leave it on the bench to rise and cover the jar with a tea towel or loosely balanced lid.

Add raisins and orange zest to a small bowl. Heat the orange juice and pour it over it. Leave these to sit and hydrate for 20-30 minutes.

Mix flour, sugar, spices, salt, eggs, milk, and sourdough starter in a large bowl. Use a fork to combine it into a shaggy dough.

Add softened butter, raisins, orange juice, and zest. Use your hands to squish everything together until the butter is incorporated.

Transfer the sticky dough to a clean, lightly greased bowl once the butter has been mixed in.

Perform 4-5 stretches and folds over the next two hours—one every 20 minutes.

A stretch and fold method stretches one side of the dough and pulls it over itself. The bowl is then turned a quarter turn, repeated on the following side. Continue stretching, folding, and turning the bowl until all sides have been folded. You can do a few extra turns if needed. That is 'one set' of stretch and folds. (The dough can also be mixed in a stand mixer with a dough hook for 10 minutes.)

After the dough has been kneaded, cover the bowl with plastic wrap or a damp cloth and let it rise in a warm spot, ideally at around 77°F/25°C, until bulked out by about 50%.

You can create a warm and humid spot for this bulk rise by placing the bowl in a turned-off oven alongside a large cup of boiled water.

After this, place the dough in the refrigerator in an airtight container

Option 1- The dough can be refrigerated overnight after the bulk rise. The next morning, let the cold dough sit for 10 minutes at room temperature, then the buns can be shaped and rise until doubled, ideally at around 25°C/77°F. This can take between 4- 8 hours, depending on temperature. Bake them once they're doubled in size.

Option 2 - The buns can rise overnight if your kitchen isn't too warm. Let the dough sit in the fridge for the rest of the day, then in the evening, remove it and shape the buns. Cover them with a damp tea towel or plastic wrap and let them rise overnight at room temperature for 8-10 hours. They can be baked fresh in the morning.

Pull the dough from the bowl onto a lightly floured bench and cut it into 9 or 12 even-sized pieces. Dust your hands with flour if needed and shape the pieces into balls, tucking in the bottom to create a smooth top.

Place the balls, seam side down, into a greased or parchment paper-lined dish, (I use a 23x23cm square, but you can also use a larger tray.) Let them rise until doubled.

Preheat the oven to 190°C / 375°F.

Mix the flour with enough water to make a thick paste, then add to a piping bag with a small round tip. Then pipe crosses over the buns.

Place the buns into the oven and bake for 25-28 minutes until deep golden brown.

While the buns are baking, mix the glaze ingredients until the sugar dissolves. Bush the hot bun tops with the sugar glaze once they come from the oven.

Leave the buns to cool for about 20 minutes before eating.