This is a recipe that has been in my family for years and years. These cookies are cake-like, light, fluffy and moist with zing from using sour milk. If you're looking for a classic chocolate chip cookie recipe, I must enunciate (due to two reviewers' comments) that these cookies ARE NOTHING LIKE A CLASSIC CHOCOLATE CHIP COOKIE. They are not expected to be crisp or chewy, and the flavor is much lighter. I think this is due to reduced fat content (using 1/2 cup shortening rather than the amount of butter in a classic chocolate chip cookie). I use mini chocolate chips, since regular chocolate chips tend to be too heavy for this cookie batter (but feel free to use your preference). Also, I use homogenized/pasteurized whole milk, but my grandmother always used real sour milk when we lived on the dairy farm. She didn't need to spoil the milk using vinegar. I think the type of milk makes all the diffference. These cookies are great, but they don't quite taste the same as when Grandma made them using more conventional/natural methods.