Preheat the oven to 350 degrees.
Melt the butter in a bowl in a microwave for 30-60 seconds.
Place in a large bowl or stand mixer. Beat together with the brown sugar, egg, and vanilla extract.
Mix together the flour, salt, and baking powder together in another bowl.
Sprinkle the dry ingredients into the wet ingredients. Beat until fully combined.
Add in the chocolate chips and chopped sea salt chocolate caramel squares. Combine together using a spatula.
Grease an 8x8" casserole dish with a stick of butter (simply smear cold butter on the pan).
Scrape the blondie batter into the pan. Even and flatten out the batter using a rubber spatula.
Bake for 27 minutes.