In batches of 6-8, place the pretzel nuggets in the boiling water for 30 seconds. Remove them from the water using a large flat spatula. Place them on the sheet pans, brush the top of each with the beaten egg yolk and water mixture, and sprinkle with coarse sea salt.
Bake for 12-14 minutes or until golden brown. Transfer to a cooling rack for at least 5 minutes before serving or let cool and reheat in the oven before serving.