1/2 gallon milk (you can choose whole, 2%, or skim depending on your taste)

Pour milk into a large saucepan, and heat until almost scalded (little tiny bubbles forming on the top of the milk, but not foaming or boiling).  Then let cool until body temperature.  Stir in one large tablespoonful of plain yogurt with active cultures (for my first batch of homemade yogurt I used a bit of Butterworks yogurt as the starter).  Mix into the warm milk.  Pour into a container (I use a large 1/2 gallon mason jar, or you can use a series of smaller jars).  Wrap mason jar in a blanket and leave in a warm spot overnight.  By the next morning the milk should have "yog"ed.  Mix well in the jar, and refrigerate (if you think it is still too runny, leave out for a while longer).  It's that easy!

Of course you can always add flavorings as well- favorites include maple syrup, strawberry jam, raspberry jam, elderberry jam, and rhubarb compote made with maple syrup.