I want to bake the famous Nick's supernatural brownies. I stocked up on Ghiardelli chocolate bars but not enough- I have 4 oz bars. The recipe calls for 8 oz. bittersweet chocolate (60%) and I only have one 4oz bar. But I do have 4 oz of Bakers Semi-sweet Baking chocolate at 56%. Should I go for it or wait until I can get to a store for another bar of bittersweet? I really want these brownies to live up to their reputation and I don't have good instincts when it comes to baking so thanks in advance.