I write like a scientist...: Peanut Butter Brownies

Confession time. I freaking love peanut butter. With a depth of passion that it is indecent for a woman to love a spread. I think it came to a head when I travelled to the US with my favourite Aunt, Maggie when I was ten and discovered that Americans have an entirely different relationship with PB than Aussies. There were peanut butter M&Ms, Reese's Pieces and many other permutations of the creamy, nutty spread that I hadn't even known I was missing in Australia. Sadly I had to adapt to life without Butterfingers et al, but my Mum indulged my peanut butter obsession with a Women's Weekly recipe, Peanut Butter Crinkles. Those biscuits are just delicious with the right amount of creamy nutty goodness offset with a little lemon zest and they have been a favourite since I was a little kid. But woman can not live by Crinkles alone. I need more and various ways to satisfy my peanut butter cravings! Fortunately I have discovered a new food blog, and already sunk many hours in to drooling over the gorgeous food p0rn photography and delicious recipes. This one in particular piqued my interest, enough to get my butt off the couch and into the kitchen:
Smitten Kitchen, peanut butter brownies Thank-you, Deb of Smitten Kitchen.

Peanut Butter Choc Chip Brownies
Adapted very slightly from Smitten Kitchen (mainly for ease of converting Imperial to Metric, and because I'm a bit slack and didn't read the recipe properly)

Ingredients:
250g butter, softened in microwave
1 3/4 cups caster sugar
1 cup peanut butter (I used crunchy because I like it on my toast, but next time would definitely go creamy)
2 large free-range eggs
2 cups of plain flour
250g chocolate chips (I used dark, but would give milk a go next time)

To make brownies:
Preheat oven to 180 celsius. Grease a 20cm x 30cm baking pan, then line with baking paper and grease the paper.
Use electric mixer to beat butter and sugar until pale and creamy. Add peanut butter and beat until incorporated. Beat in eggs, then add choc chips and stir until combined. Add flour and stir until just combined.
Spread batter into baking dish, smoothing the top with a spatula or damp hands.
Bake until brownies are golden brown and a bit puffy - mine only took 30 minutes and were already getting a bit overly golden on the edges.
I let mine cool in the pan overnight, but I think I would have been better to cut them to size after an hour of cooling.