My recommendation is to make the pastry cream at least a day in advance, then the cakes (the day of, or the day before you plan to assemble the cake), toast the almonds after you've baked the cakes, cut the cakes after they've cooled, assemble them with the pastry cream, make the buttercream, frost the cake, then make the almond topping and put it on the cake. I know, it's a lot of steps, but the end result is certainly a show stopper! It is a massive cake meant for a crowd, for special occasions. (I made it for my partner's birthday.) Keep that in mind as you scroll through the ingredients and realize you need seven sticks of butter, ten eggs, and more than four cups of sugar!
By the way, if you don't need to bake gluten-free, you can make this recipe more easily (and cheaply) by simply using 3 cups of cake flour instead of a GF flour mix and xanthan gum.
Burnt Almond Torte
serves at least 16