Preheat oven to 325° F. Prepare baking sheets and line with parchment paper, or foil.
Cream butter until smooth then add peanut butter and both sugars and beat until combined well. Add eggs and beat well.
Stir in flour and baking soda gradually until well combined, then Stir in chocolate chips.
Using a spoon, scoop out small portions of dough and drop onto cookie sheets, leaving about a 2" gap between each cookie.
Bake for about 15-20 minutes or until cookies are just firm around the edges- don't overbake- if you wait until they are brown on top, they will be too hard.
Notes
A general note, I did indeed bake them till they just started to brown on the edges and top, and mine turned out just fine, not too hard at all. But of course, all ovens vary.