Preheat the oven to 350°F. Lightly spray or line an 8x8-inch baking pan with parchment paper.
In a small saucepan, melt the butter and ¾ cup of the butterscotch chips, stirring over medium heat. Once they have melted together, remove them from the stovetop and stir, making sure there aren’t any remaining unmelted chips.
¼ cup salted butter, 1½ cups butterscotch flavored chips
Let the mixture cool for about a minute, then quickly whisk in the sugar and the eggs.
1 cup brown sugar, 2 large eggs
Once the sugar and eggs are well combined with the melted chips, add in the flour and vanilla. Continue mixing all of the ingredients together until the batter thickens, scraping the sides of the bowl if needed.
1 cup all-purpose flour, 1 teaspoon pure vanilla extract
Fold in the remaining ¾ cup of chips, evenly distributing them throughout the batter.
Pour the batter into the prepared cake pan and spread it evenly with a spatula.
Bake for about 25-30 minutes. Remove from the oven and allow the blondies to cool before cutting them.