Line an 8x8-inch baking pan with 2 sheets of parchment paper long enough to extend over the sides of the pan to make a sling. (This will make removing the brownies from the pan easier.)
Heat the butter in a small saucepan over medium heat. When you see the butter start to foam, stir with a soft silicone spatula, scraping up any bits from the sides and bottom of the saucepan.
1 cup unsalted butter
Continue stirring until the butter has turned a medium golden brown (approximately 6-8 minutes), then remove the saucepan from the heat and pour the browned butter (with all the bits) into a large heat-proof bowl.TIP - To ensure you don’t burn the butter take the saucepan off the heat at the first sight of it turning medium-golden. The butter will continue to darken in the saucepan until it gets poured into the heat-proof bowl.
Add the brown sugar and vanilla extract and stir to combine.
1 1/2 cups dark brown sugar, 2 teaspoons pure vanilla extract
Stir in the eggs and set aside.TIP - When adding the eggs to the butter/sugar mixture, ensure it is not too hot (you don’t want to ‘cook’ the eggs).
2 large eggs
In a medium-sized bowl, whisk together the flour, baking powder, and salt.
1 3/4 cups all purpose flour, 1/2 teaspoon baking powder, 1/2 teaspoon salt
Add the flour mixture to the butter/sugar mixture, stirring until the ingredients are well combined.
Fold in the toasted pecans and butterscotch chips.
3/4 cup toasted pecans, 3/4 cup butterscotch chips
Transfer the batter to the prepared baking pan, spreading it out in an even layer and making sure to get the batter into all the corners.
Bake for 20 to 25 minutes, checking to ensure that the brownies are not overbaking. They should be golden along the edges while the center is still soft.
Remove the brownies from the oven and place the baking pan on a wire rack to cool for 30 minutes before slicing.
If using Kosher salt, increase the salt to ¾ teaspoon.
Putting clips to hold down the parchment paper makes spreading the thick brownie batter easier.
You can easily substitute with either chopped almonds or walnuts if preferred. For a nut-free version, simply replace the nuts with extra butterscotch chips.
If you want a more ‘wet’ brownie, take them out of the oven when they are lightly golden brown around the edges and the middle is still soft. Then, remove the brownies from the pan and let them cool on the counter. If you leave the brownies in the pan, they will continue to bake and set while they cool.