Peanut Butter Swirl Brownies by Jools

I’m a health freak so when it comes to treats I want them decadent but not stuck on my hips for the next 3 weeks. Read this on why I stopped eating sugar cane
This brownie is an adaptation of a few recipes I found and that were sent to me.
I only made half and will be freezing the rest. I like eating them when they are half frozen. They have that ice cream feeling about them.

24 servings at 277 calories per serving! Not bad, uh?

1 cup (2 sticks) butter, plus extra for greasing the dish.
8 ounces bitter-sweet chocolate . I use 85% dark chocolate
5 eggs
1 1/2 cups agave nectar or 3 cups sugar
1 tablespoon vanilla
1 teaspoon salt
1 1/4 cups (6.38 ounces) flour
1/4 cup cocoa
3/4 cup organic crunchy peanut butter. (no sugar added)

Heat the oven to 350 F/ 175C. Grease a 9-by-13-inch glass baking dish.
In a medium, heavy-bottom saucepan, melt the butter and chocolate over low heat, stirring occasionally. Remove from heat and set aside.
In a large bowl using an electric mixer, beat together the eggs, agave nectar or sugar and vanilla until light and fluffy, 5 to 7 minutes.
Fold in the melted chocolate, then the salt and sifted flour & cocoa just until combined.
In a small ball beat the peanut butter until soft.
Pour the batter into the prepared pan. Put dollops of peanut butter & using the tip of a sharp knife swirl into the mixture.
Bake in the center of the oven until puffed and almost set, about 35/40 mins. A toothpick inserted will be slightly moist. Remove and cool slightly before serving.