Red Velvet Brownies with White Chocolate Buttercream

What's even better than homemade brownies?
Homemade red velvet brownies!

What's even better than homemade red velvet brownies?
Red velvet brownies topped with a decadent white chocolate buttercream.  Delicioso!

I went to a birthday party today and was charged with finding the perfect dessert to bring.  When I came across these brownies on Smells Like Home, I knew my search was over.  They were the hit of the party- moist and sinfully chocolatey.  I was worried that the frosting would be too sweet based on Tara's review, so I used an alternate buttercream recipe.  I was glad I did- the simple combination of butter, melted white chocolate, and a touch of powdered sugar was pure perfection.

Red Velvet Brownies, as seen on Smells Like Home, originally from How Sweet It Is
White Chocolate Buttercream, adapted from Grace Parisi

INGREDIENTS
For the brownies:
3 tbsp unsweetened cocoa powder
2 oz red food coloring (I used 1 oz)
2 tsp pure vanilla extract, divided
1/2 cup (8 tbsp) unsalted butter, at room temperature
1 1/2 cups granulated sugar
2 large eggs, at room temperature
1 1/4 cups all-purpose flour
1/4 tsp salt

For the white chocolate buttercream:
5 tbsp unsalted butter, softened
4 oz good white chocolate, melted and cooled slightly
1/3 cup powdered sugar
Splash of vanilla extract, optional

DIRECTIONS
For the brownies:
1.  Preheat the oven to 350 degrees F.  Butter and flour an 8″x8″ baking pan.
2.  In a small bowl, slowly stir together the cocoa powder, food coloring, and 1 tsp vanilla into a thick paste until not lumps of cocoa remain. Set aside.

3.  In the bowl of a stand mixer fitted with the paddle attachment, beat together the butter and sugar on medium speed until light and fluffy, about 2 minutes.  Add eggs one at a time, mixing well after each addition, then stir in the remaining 1 tsp of vanilla.  With the mixer off, add in the cocoa mixture, then turn the mixer to medium and beat the two mixtures together until they are one uniform color.  Slowly add in the flour and salt and mix on medium-low speed, just until combined.  Do not overmix.

4.  Remove the bowl from the mixer and stir up the batter with a rubber spatula once or twice just to ensure all of the flour has incorporated from the sides of the bowl and there isn’t anything stuck on the bottom of the bowl.  You’ll want one uniformly colored (red) batter.

5.  Pour the batter into the prepared pan and bake for 25-30* minutes or until a toothpick comes out clean when inserted into the center of the brownies.  Allow brownies to completely cool in the pan on a baking rack, about 45-60 minutes.  Frost brownies in the pan, cut into 12 bars, and serve, or remove the entire batch from the pan to a cutting board, cut into 12 bars, frost, and serve.

*Note- My brownies took about 45 minutes.

For the frosting:
1.  In a medium bowl, use a handheld electric mixer to beat the butter at medium speed until creamy. Beat in the melted white chocolate. Add the confectioners' sugar and vanilla and beat at low speed, scraping the sides and bottom of the bowl, until light and fluffy.