So what exactly are Sourdough stretch and folds? ? When this technique is used correctly, it will not only strengthen gluten development in sourdough bread, but it will also add air into your dough without traditional kneading.

Typically I suggest doing stretch and folds a number of times, especially when making a boule.  This process is completed after the mixing stage, during what we call the bulk ferment stage.   While your dough sits out, and your starter begins to produce gas your stretch and folds  are completed usually between 30 to 45 minute time intervals.  During this process, you'll experience a magical transformation in your dough.  It will go from a shaggy, sometimes sloppy mess... to a light, airy and silky ball.  When completed correctly, you'll be rewarded with an amazing oven spring and even in some cases a wonderful lacey crumb.

Why are Stretch and Folds Important?
Completing stretch and folds is important because not only are you developing strength and gluten within your dough, you are incorporating air and moving the natural yeast (and food around).   This helps create strength with your dough which aids with rise in the oven!  During this process, it's particularly important to ensure that you are only pulling your dough until you feel resistance, you do not want to end up ripping the  gluten fibers your working hard to build.

How to do Stretch and Folds
The action is simple, grab the edge of your dough, and stretch it until you feel resistance.  Then fold it over.  Basically you are stretching the dough and folding it over itself.  Repeat this all the way around your dough until you can no longer stretch it without ripping it.  Bakers will complete this 4 - 6 times within the first 2 hours of the bulk ferment.  During this time your dough will transform into beautiful and soft dough.

Coil Folds
In some instances with really high hydration dough, it is almost impossible to work with. This is when a coil fold is particularly helpful, like in the case of making Ciabatta.  To perform a could fold, first wet your hands with water -- this will prevent the dough, for the most part, from sticking to your hands.  Then, scoop the dough up with both hands and allow the rest to droop back into the bowl while gently laying it back on top of itself.  Turn your bowl 90 degrees and perform again, until you've gone around all sides.