World's Best Peanut Butter Cookies

This recipe was created by a friend of a friend when she was in high school. Andrea had a chronic illness and died suddenly while she was in college. They really are exceptional cookies.

Cream together with electric mixer on medium speed:
1/2 C shortening (I used coconut oil, which is solid at room temp, instead)
1 C creamy peanut butter (I used Adams all natural)
3/4 C sugar (I used Splenda granulated)
1/2 C brown sugar
1 tsp vanilla

Add 1 egg and 1 Tbsp milk and beat until well-blended.

Combine separately:
1 1/4 C flour
3/4 tsp baking soda
1/2 tsp baking powder
1/4 tsp salt

Add to wet ingredients and mix all well together. Form rounded balls of dough and place on ungreased baking sheet. Flatten with a fork in a criss-cross pattern. Bake at 375 for 8-10 minutes.