Preheat oven to 350 degrees. Grease an 8x8 pan then lay a piece of parchment paper on the bottom of the pan. Spray the parchment paper with nonstick cooking spray.
In a saucepan, add the butter and sugar. Over medium heat, melt the butter and sugar. Whisk occasionally.
Once the butter/sugar mixture is melted, remove the saucepan from the heat.
Pour the white chocolate chips and cream cheese into the saucepan and let them sit for a minute. After the minute, start whisking until combined. It will take a minute or two of whisking.
Add the eggs into the mixture and continue whisking until they're incorporated.
Add in the vanilla and flour and continue whisking.
Pour the batter into the prepared 8x8 baking pan.
Place into the oven for 30 minutes or until done. Place a toothpick in the center of the brownies and if it comes out clean, they're done.
Let the brownies rest in the pan for 10 minutes and then turn them out onto a cooling rack.
Frosting
In a mixing bowl, add the butter and peanut butter. Beat with a hand mixer on medium until incorporated.
Pour the vanilla and powdered sugar into the bowl. Mix on low until the powdered sugar is incorporated.
Add 1 tablespoon of heavy cream at a time and mix until the frosting is the perfect consistency. You can add or subtract as much heavy cream as you would like.
Slather the frosting on the cooled brownies. Cut and eat.