Peanut Butter Swirl Bars

I made these simple bars the other night and they were really good! For some reason my chocolate chips didn't melt, so the swirling thing never happened, but, no matter, they were still delish. The crust is soft and crumbly, like a shortbread, and the peanut butter icing was amazing on the top.

Bars:
1/2 C. butter (1 stick), softened
1/2 C. granulated sugar
1/2 C. firmly packed light-brown sugar
1/2 C. creamy peanut butter
1/2 tsp. vanilla extract
1 C. flour
1 C. quick-cook oats
1/4 tsp. salt
6 oz. chocolate chips (about 1 C.)

Icing:
1 C. confectioners' sugar
1/4 C. peanut butter
3 Tbsp. milk

1) Heat oven to 350. Coat a 13x9x2 inch pan with cooking spray
2) In a large bowl, beat the butter, sugars, peanut butter and vanilla until smooth.
3) In a second bowl, whisk together flour, oats, and salt. On low speed, beat flour mixture into butter mixture until just combined. Press dough into prepared pan. Evenly sprinkle chocolate chips over the top.
4) Bake at 350 for 20 minutes. Remove from oven.
5) Make Icing: In a medium-sized bowl, blend confectioners' sugar, peanut butter, and milk until smooth. Pour icing over the uncut bars while still warm and swirl chips with icing. Cool completely in pan and cut into 16 bars.