This is such a terrible photo that I'm only going to include a tiny glimpse of it, but it's such a great brownie that I'm still going to give you the recipe.
Marbled Peanut Brownies
1 c. butter
11 oz. semi sweet chocolate chopped into smallish chunks
1 1/3 c. flour
1 tsp. baking powder
1 1/4 c. sugar
6 large eggs
2 tsp. vanilla extract
In a bowl over simmering hot water, melt butter and chocolate. Add sugar, stir well. Beat in eggs one and a time, then add vanilla. Mix up flour and baking powder and add that as well.
Peanut Butter batter:
1/2 c. melted unsalted butter
1 c. icing sugar
1 1/2 c. peanut butter
1/2 tsp. salt (don't forget this - it adds a really amazing taste sensation)
more vanilla extract
Stir everything together in a separate bowl.
Lay a sheet of parchment paper on a cookie tray, then pour a little over half the chocolate brownie batter on the parchment, spreading it out to the edges. Then get your peanut butter batter and drop teaspoonfuls all over, about an inch apart. Then drip what chocolate batter you have left over top of all this. It will look messy and sort of weird. Don't fret.
Then take a long knife-like object and pretend you are slicing this mixture from one end to the other, until you've 'cut' the peanut butter rather artistically (ie: nice swirls instead of globs) into the chocolate mixture.
Bake 325ºF for about 30 minutes. I kept putting the timer on for 10 minute intervals and checking it, but I prefer my baked goods slightly underdone (keeps them moist), so just keep a close eye on yours.
When this was slightly cooled I melted a few ounces of chocolate (again in a double boiler) and drizzled it over top of the brownie. Then I chilled it and sliced it up. I also kept ours in the fridge between bites - but it's hot here right now and things melt quick.