Mix the first three ingredients, let stand for 10 minutes. Mix the warm milk, egg, salt, yeast mixture and flour. Add the bread cubes. Add more flour, if necessary, until you have an elastic-y type bread dough. Knead the resulting dough just as you would when making bread. Cover with a cloth and let the dough rest in a warm place to rise. It should double in about 2 hours. Knead again and divide into 4-5 sections. Roll each section into a log, each about 1 1/2" thick and 7-8" long. Let rise another 1/2 hour. Drop the logs of dough, one at a time, into a large kettle of boiling water with a tight fitting lid. Boil gently on med-lo for about 10-12 minutes. DO NOT LIFT THE LID!! Remove with slotted spoons and place on a buttered platter. Keep warm by draping a cloth over them. When ready to serve, slice 3/4" thick with a sharp knife.