Returning to my question I posted here a few years ago . . .
Later on I found a great article on Sunset.com :
The perfect chocolate chip cookie . . . where a paragraph discusses :
What makes cookies soft and chewy?
High moisture content does; so the recipe, baking time, and temperature must be adjusted to retain moisture.
Binding the water in butter, eggs, and brown sugar (it contains molasses, which is 10 percent water) with flour slows its evaporation. The dough needs a little extra flour, which makes it stiffer. The stiff dough spreads less, less liquid evaporates, and the cookies are thicker.
Mass also helps cookies stay moist--big dollops of dough make softer and chewier cookies than tiny spoonfuls of dough. Bake these thick cookies for a shorter time at a high temperature to firm them quickly and minimize spreading. Most important, don't bake them too long--remove from the oven when the cookie rim is brown and at least 1/3 of the center top remains pale. The cooked centers will be soft.
What makes a cookie crisp or crunchy?
Reducing the amount of ingredients that hold moisture--flour, egg, and brown sugar--makes it easy for liquid to evaporate, producing crisp cookies.
So to make a cookie more chewy, from all the info that I've found (including here) . . . . if the amount of flour is kept constant, then I gather you need proportionally . . . :
(And I am not a professional or expert cook by any means, just trying to make sense out of what I've read. If anyone knows better please correct me.)
- more sugar, especially brown sugar. (this is the one thing I notice in all the "chewy" recipes - they all have more brown sugar)
- more eggs (?), or at least extra egg yolk. It seems that more of whole egg will make the cookies both chewy and thicker.
- more gluten development
- slightly less liquid (liquid makes the cookies spread)
However - and this is important - a primary objective is to have the dough retain moisture. But the way to do it is not to just add liquid itself.
- less baking time but higher baking temp
- melting the butter (adding this from the "chocotuile" suggestion below, and from the "The Perfect Chocolate Chip Cookie" article/recipe cited below.
- less fat (although I see some recipes using slightly more. In general more fat creates more internal heat which drives out the moisture, and it also causes the cookies to spread, making them thinner and crispier. )
Maybe someone reading this can clear up some of the ambiguities.
Edited by kbarb - 11/30/11 at 12:47pm