CHOCOLATE MOUSSE CAKE WITH RASPBERRIES

Steps:

• Preheat the oven to 325°F. Lightly grease two 8" round pans at least 2" deep (and preferably 3" deep); four 8" round pans at least 1 1/2" deep; or three 9" round pans. If you have parchment rounds, line the pans with parchment, and grease the parchment. Note: If your pan assortment doesn't include any of these particular combinations, you can bake the cake batter in batches; the unbaked batter won't suffer while awaiting its turn in the oven.
• To make the cake layers: Weigh your flour; you'll find its weight by toggling to "ounces" at the top of the ingredient section above. Or measure it by gently spooning it into a cup, then sweeping off any excess. Whisk together the flour and remaining dry ingredients in a large mixing bowl; or combine thoroughly using a stand mixer equipped with the whisk or beater attachment. Check to make sure there aren't any hard lumps in the mixture; if there are, press them through a sieve.
• Combine the oil, buttermilk or yogurt, boiling water and vanilla in a medium bowl or large measuring cup. Add to the dry ingredients and beat at medium speed for 30 seconds to 1 minute, until the batter is smooth.
• Scrape the sides and bottom of the mixing bowl, then beat in the eggs one at a time. Mix on medium speed for another minute, or until smooth.
• Divide the batter among the prepared pans. Bake for 45 to 50 minutes for two 8" pans; or 25 to 30 minutes for four 8" pans or three 9" pans, until the cake just begins to pull away from the edge of the pan, and a tester inserted in the center comes out with just a few moist crumbs. Remove from the oven and place on a rack to cool for 15 minutes. Run a table knife around the edge of each pan to free the crust, and turn the cakes onto the rack to cool completely. While the cake layers are cooling, make the filling.
• To make the filling: In a large mixing bowl, combine the butter, cream cheese, 3/4 cup (3 ounces) of the confectioners' sugar, vanilla, and salt, mixing at medium-low speed until smooth. Melt the chocolate; a minute or less in the microwave should be sufficient to soften the chips enough that you can stir them until completely melted and smooth. Add the melted chocolate to the bowl and mix on medium-high speed for 1 minute, or until a bit lightened and fluffy.
• Whisk together the remaining 1/4 cup confectioners' sugar with the Instant ClearJel. Beat the heavy cream until soft peaks form, then add the confectioners' sugar mixture. Beat just until the cream is stiff; guard against over-beating, which will turn the cream grainy. Fold the whipped cream into the cream cheese mixture; scrape the bowl, and stir to combine any sticky residue. Finally, fold in the chocolate mini chips, if you're using them.
• Split the cake layers horizontally if you've baked two deep 8" cakes; trim any domes off the tops if you've baked three or four individual layers. Place the first layer on a serving plate (line the edges with strips of waxed or parchment paper to keep the plate clean), and spread it with one-third of the filling (1 cup; 7 5/8 ounces; 216g). Cut 1/2 pint of raspberries in half lengthwise (rather than around the circumference), and place them over the filling, covering its entire surface. Repeat until all the layers are stacked; place the last layer bottom-side up for a flat surface on top.
• Once the layers are assembled with filling and raspberries, place the cake in the refrigerator or freezer for at least 30 minutes to firm it up. This will make frosting the cake much easier since the layers are less likely to slide around and chilling helps prevent the cake from shedding crumbs as you frost. While the cake is chilling, make the frosting.
• To make the frosting: In a large bowl, beat together the butter, and salt.
• Sift the confectioners' sugar and cocoa through a strainer to remove any lumps, and gently beat into the butter mixture alternately with the milk. Add the vanilla. Beat on medium-high speed for 2 minutes, or until fluffy.
• To finish the cake: For the best-looking cake, do the frosting in two steps. First, spread a very thin layer of frosting around the sides and across the top; this is called a crumb coat. You should actually be able to see the cake through the frosting in spots, it's that thin. Refrigerate the cake for 20 minutes to let this layer set up.
• Once the cake is chilled, use the remaining frosting to coat it thoroughly and evenly. The frosting will be thin, but the cake should be completely coated, with no bare patches. If you have any leftover frosting, use it to pipe decorations on the top and/or around the base.
• Refrigerate the cake until ready to serve. Garnish with fresh raspberries just before serving.
• Store any leftovers in the refrigerator for up to 3 days; freeze for up to a week.