Preheat the oven to 350F. In a small saucepan, melt the butter over medium heat. Keep it on the heat, stirring occasionally, until the foam starts turning golden and the mixture smells nutty. If you've never browned butter, go here. Remove from heat and pour immediately into a mixing bowl. (Hurry, otherwise the heat from the pot could burn this precious stuff.)
Stir in the brown sugar, then the vanilla, then the eggs. Add the flour, baking soda and salt and stir until almost combined; add the chocolate and stir just until there are no more streaks of flour.
Spread into an 9×13-inch pan and bake for 23-27 minutes, until golden and set. (Or until golden and gooey...aka not quite set.) Serve warm or cool in the pan on a wire rack.
Notes
The original recipe only makes a square pan. And it says it make 16 blondies. Hahahahaha. This recipe is written to make a 9x13. You're welcome.Source: Dinner with Julie