Preheat the oven to 350°F. Line a 7x11 inch baking pan with foil or parchment paper, leaving a slight overhang.

In a medium pot, melt 6 tablespoons butter over medium heat. Pour the butte into a large bowl and whisk in the sugar. Set aside to cool for 5 minutes.

Once the mix has cooled to room temperature, whisk in the oil, vanilla extract and the eggs. Evenly sprinkle the flour on top, then the baking powder and salt. Carefully mix into the egg mixture until a batter forms. Fold in the cranberries and chopped walnuts.

Pour the batter into the prepared baking pan and sprinkle the top with more chopped walnuts, if you like.

Bake at 350°F for 30-35 minutes or until the top turns golden brown and a toothpick inserted comes out clean.

Cool in the pan on a wire rack before slicing into 12 squares.