Step 1

In a stand mixer fitted with a dough hook, combine all the bun ingredients except the egg wash.

Step 2

Mix on low speed for 2 minutes, then on high speed for 5 minutes until a smooth dough forms.

Step 3

Transfer the dough to a large bowl, cover with cling film and a kitchen towel, and leave to prove in a warm place for 1 hour.

Step 4

After an hour, punch down the dough and knead briefly on a floured surface.

Step 5

Divide the dough into 100 g portions.

Step 6

Roll each portion into a smooth ball and place them on a baking tray lined with parchment paper, spaced 5 to 7 cm apart.

Step 7

Cover with a clean towel and leave to rise again until puffy and nearly doubled, about 1 hour.

Step 8

Preheat the oven to 220°C.

Step 9

Brush the tops of the buns with beaten egg and bake for 15 minutes or until golden brown.

Step 10

Transfer to a wire rack and allow to cool completely before slicing.

Step 11

For the ketchup, mix the sugar and agar in a small bowl. Add all other ingredients to a saucepan and bring to a boil over medium heat, stirring continuously.

Step 12

Once boiling, add the agar mixture and stir well. Continue boiling for 1 minute, then pour into a bowl and cover with cling film.

Step 13

Refrigerate until set, then blend on high speed until smooth.

Step 14

Store chilled until ready to serve.