*Add ½ tsp. vinegar to milk to sour it. Set it aside while preparing other ingredients. As it sits, it will thicken up.
Prepare the dry ingredients. In a mixing bowl, whisk together the flour, baking soda and salt. Set aside.
In the bowl of a stand mixer, cream together the butter, shortening and sugar.
Add the egg and mix well.
Add the vanilla and almond extracts and mix well.
Add the flour mixture alternately with the sour milk. Mix well after each addition.
Turn out the dough onto a large piece of parchment or plastic wrap, flatten into a disc and completely cover the cookie dough.
Chill in the fridge for at least one hour before rolling out. This will make it easier to handle.