Set oven to 350 °F.
Grease a 9 by 13 inch pan.
Cream butter and sugars together.
Beat in eggs and vanilla.
Add flour, salt and baking soda.
Stir in oats and raisins. (Soak dry-ish raisins in hot water for about 15 minutes. Raisins draw moisture from batter.)
Spread in the prepared pan.
Bake in preheated oven 30 minutes.
Cool slightly and cut into 32 bars.