To make this recipe in a stand mixer, combine warm water and yeast in the bowl of the mixer and let soften for about 5 minutes. Add flour, milk powder, sugar, salt, egg, and egg white. Mix on low speed using the dough hook, scraping the dough down occasionally, for 10 minutes. Add the softened butter, cinnamon, and currants and mix for an additional 5 minutes. Transfer the dough to a greased bowl, cover it with plastic wrap and a kitchen towel, and allow it to rise until doubled, about 1 hour. Proceed with the recipe instructions.