peanut butter swirl brownies (re-posted)

Very rich and delicious.

peanut butter swirl brownies (blog: Real Mom Kitchen)
1 package of brownies mix (the 9x13 inch size) plus water, eggs and oil

filling
4 tablespoons unsalted butter, melted
1/2 cup confectioners' sugar
3/4 cup smooth peanut butter
1/4 teaspoon salt
1/2 teaspoon pure vanilla extract


Preheat oven according to directions on brownie mix.  Line an 8-inch square baking pan with foil, allowing a 2-inch overhang.  Spray bottom of pan with non-stick spray.  Make batter according to directions on box for cake-like brownies (I didn't do that part).
Make filling: Stir together butter, confectioners' sugar, peanut butter, salt and vanilla in a bowl until smooth.  Pour one-third of batter into prepared pan; spread evenly with rubber spatula.  Drop dollops of half of the peanut butter filling (about 1 tablespoon each) on top of batter, spacing about 1-inch apart.  Drizzle remaining batter on top and gently spread to fill pan.  Drop dollops of remaining half of filling on top.  Gently swirl peanut butter filling into batter with a butter knife, running the knife lengthwise and crosswise through layers.  Be careful not to get the knife to the very bottom of the batter or you  may cut the foil.
Bake according to brownie mix directions for 8x8-inch pan until a toothpick inserted into brownies comes out with a few crumbs but is not wet.  Let cool slightly in pan, about 15 minutes.  Lift out; let cool completely on a wire rack before cutting into squares.  Makes 9-12 brownies.