Preheat oven to 350 degrees F. Grease the bottom of a 9x13-inch baking pan.
In a large saucepan over medium-low heat, melt the butter; remove from heat.
Add the brown sugar and blend to combine. Add the eggs, one at a time, beating well after each addition. Stir in the vanilla extract, flour, and baking powder. Stir in the chopped nuts.
Press the cookie mixture into the prepared baking pan and bake approximately 30 minutes (do not overbake). Remove from oven and let cool on a wire cooling rack before cutting.
Makes 24 squares.
Saucepan Scotchie Bars Recipe: https://whatscookingamerica.net/cookie/saucepanscotchies.htm