Preheat the oven to 175 C. Lightly grease a square 8" baking pan, line it with baking paper leaving a little overhang, then grease the paper too. Set aside.<br></br>

In a small saucepan on low heat, melt the butter till it becomes frothy, then clear, and you start to see small brown bits on the bottom of the pan and your kitchen smells like some unreal paradise. Pour into a mixing bowl.<br></br>

Stir in the sugar and whisk well till combined, then add the peanut butter and stir again. The mixture should now be lukewarm.<br></br>

Add the egg and vanilla and whisk again to combine. Beat a little vigorously here because much like in brownies, it is this step that incorporates air into the batter and helps the blondies rise and form a nice crust.<br></br>

Now add the flour and fold it in gently till combined. The batter might look a little oily so do your best to mix it well (without over mixing) but most of my Googling said since it's quite a buttery recipe with less flour to soak it all in, a little oiliness is to be expected.<br></br>

Finally, fold in the chocolate chips. Spread the batter evenly out into the pan and top with sea salt. It's not a very large amount of batter so don't worry if it looks like it won't cover the pan, just keep smoothening it out.<br></br>

Bake for 20 minutes until the top is lightly browned, then set aside to cool at room temperature. I baked them for 25 minutes and though they weren't dry, the top was a little browner than I would have liked, so stick with 20 minutes unless you see uncooked batter. You may also see some butter bubbling up around the edges which soaks in as the blondies cool. They do not rise like a cake, so don't be surprised if they aren't too thick.<br></br>

Allow the blondies to cool completely, then top with more sea salt if you like and slice into squares. Store at room temperature in an airtight tin for 4 to 5 days, then either freeze or refrigerate. Happy baking!