Preheat the oven to 350 degrees F. Line cookie sheets with parchment paper or spray with nonstick spray.
In a large bowl, combine the eggs, butter, milk and vanilla, and beat with an electric mixer. Add the peanut butter and sugars to the egg mixture. Mix well- the mixture will be a little weird until the dry ingredients are added!
Sift the flour, soda and salt into a medium bowl. Gradually mix in to the wet mixture.
Drop by small teaspoonfuls onto foiled or lightly greased cookie pans (or use parchment paper). Press down lightly with sugared fork (crisscross to make design).
Bake for 10 to 12 minutes, or until cookies are set and no longer gooey. Cool well before storing in a covered container.
Don't use natural peanut butter for this recipe. It just won't turn out the best. Creamy peanut butter vs. crunchy peanut butter is entirely your preference.
Using a sugared fork will ensure that the fork will not stick to the dough.