Stir the starter into the milk until dissolved, whisk in the egg and sugar, then add the flour and salt and knead 5 minutes by machine or 8 by hand.

Knead in the dough butter a tablespoon at a time, then 6 to 8 minutes more until smooth and glossy.

Cover and rise at 75 to 78°F (24 to 26°C) for 5 to 6 hours, until about 50% larger.

Cover and refrigerate the dough for 8 to 12 hours.

Rub the zest into the filling sugar, mix in the filling butter and the chopped cranberries, and divide into 3 portions.

Divide into 4 pieces of about 210 g, roll each into a 10-inch round and stack them with filling between the layers, leaving the top round plain.

Mark a 2½-inch center, cut 16 strips out to the edge, then twist each pair of neighboring strips away from each other twice and pinch into 8 points.

Proof 1 to 2 hours until slightly puffy, brush with egg wash and bake at 350°F (175°C) for 22 to 28 minutes, until 190°F (88°C) in the center.

Whisk the powdered sugar and orange juice, cool the star 15 minutes, then drizzle with the glaze.