You can mix the chocolate sweetness as you please. You can use all semi-sweet, all bittersweet or mix as you wish. However, make sure to use 10 ounces of the chocolate total. Cake boards are very useful when making any kind of cake, so be sure to have some on hand. Leave the slice out for about 5-10 minutes, so the mousse can melt a bit, then enjoy! Blowtorch, french knife, cake board, and springform pan are just some of the tools I'd recommend for this recipe.