Preheat oven to 350 F. Grease and flour a rectangular baking pan. Add both flours, salt, baking soda and oats to mixing bowl and stir together.

Add butter and vanilla extract and beat with electric mixer for about a minute. Add the sugar and beat some more until the mixture is crumbly. It should *not* come together like most batters.

Pour a little more than half the crumbly batter to the bottom of the baking pan and spread evenly, gently pressing (really gently). Bake for about 15 minutes or until very light golden brown.

Remove from oven and sprinkle marshmallows and chocolate chips across the top.

Top that layer with the remaining batter, gently pressing again, paying attention to “tuck” the marshmallows a bit since they can get a little crispy if they are poking out (not that it’s a bad thing).

Bake for another 15 or so minutes until golden brown. Let cool and cut in squares.