Pour milk into the microwave safe bowl and cook for about 2 minutes, checking at 60 seconds. Add butter chunks to melt in the hot milk, and let it cool to lukewarm.
In the large mixing bowl, stir yeast in with the flour. Stir together the warm water, sugar, and salt and add to the cooled milk mixture. Make a well in the flour and pour in the liquids. Stir until the mixture forms a soft dough. Add more flour if it's sticky, about ¼ cup at a time. Dough should be soft and pliable, not stiff.
Turn out the dough onto a floured surface and knead in more flour until it is stiff and just barely sticks to the fingers, about 5 minutes. Put the dough in a covered bowl in a warm place and let rise until doubled, about 2 hours or more.
After the first rising, divide the dough into three pieces. Roll each piece to form a rectangle about twice as long as wide. Sprinkle cinnamon and sugar mixture over the surface of the dough. Fold the two long sides over to meet in the middle. Then starting at the bottom, roll it up until you have something like a thick stick. Place in greased loaf pans. Repeat with the other pieces.
Cover with a towel and let rise again until doubled, 30 to 60 minutes.
Preheat oven to 375° F. Bake for about 30 minutes, until the tops are golden brown and sound hollow when tapped. Remove from pans and set to cool on a wire rack.
VariationsActive dry yeast: Use one packet. Dissolve the yeast in the warm water, along with the salt and the sugar. Stir in a cup of flour and let set until bubbles form. Add cooled milk mixture and stir in flour until you can't stir anymore.