Using hand mixer or stand mixer with paddle attachment: Cream the softened butter and both sugars together on medium speed until smooth (2 minutes)
Add eggs and mix until combined, scraping down sides of bowl (1 minute)
Add vanilla and molasses and mix on high until combined, set aside
In a separate bowl, whisk the flour, baking soda, cinnamon and salt together
Add the wet ingredients and mix on low until combined
Beat in oats, raisins (and walnuts) on low speed
Dough will be thick, very sticky
Chill dough for 30-60 minutes in refrigerator - if you chill longer than this (up to 2 days)
