Mix all dough ingredients in a large bowl to form a stiff dough.
Knead dough for 10 minutes by hand or 5 minutes with a dough hook until elastic.
Divide dough into 12 balls and let prove under oiled cling film for 25 minutes.
Make a hole in each ball and prove for a further 35 minutes.
Preheat oven to 230°C.
Poach bagels in boiling water for 75 seconds per side in batches.
Dry bagels on a rack and glaze with beaten egg.
Bake on greased trays for 10 minutes then swap trays and bake for 5 more minutes.
Temper white chocolate over a pan of simmering water until it reaches 43°C.
Drizzle melted chocolate in a zig-zag pattern over cooled bagels.