Milk Stout Chocolate Cake

Directions

1. Preheat oven to 350 degrees. Line two 9 inch cake pans with parchment then butter and dust with cocoa powder. Whisk together cocoa powder, flour, salt, baking soda and baking powder. Place sugar and eggs in a mixer fitted with blade attachment and process until thick and creamy. Add buttermilk and Fustini&rsquo,s Espresso Bean vnegar and mix well. Add flour mixture and with mixer on low, add hot beer. Do not over-mix. Divide batter between cake pans and place into the hot oven. Bake until a toothpick comes out clean, approx 35-40 minutes. Let cool on rack 30 minutes then unmold, remove the paper and let cool completely.
2. Place sugar and butter in a mixer fitted with the blade attachment. Add cocoa powder, Fustini&rsquo,s Vanilla Balsamic Vinegar, and Milk Stout then process on low. Add enough milk to make the right consistency. Use immediately.
3. Combine 6 ounces (3&frasl,4 cup) water, corn syrup, sugar, and salt in a 3-quart stainless steel pot and set over medium heat. Stir the mixture with a fork until bubbling, about 5 minutes, then increase heat to medium-high. Clip-on a digital thermometer and cook, without stirring, until the clear syrup registers 250°,F, about 8 minutes.
4. Transfer the thermometer to the bowl of a stand mixer and pour in the hot syrup all at once, scraping the pot with a heat-resistant spatula. Cool to exactly 212°,F, about 8 minutes, then add gelatin. With the whisk attachment, mix on low speed until the gelatin is melted, then increase to medium-high and whip until thick, snowy white, roughly tripled in volume, and beginning to ball up around the whisk, about 10 minutes. Scrape into a greased 4-cup container, cover tightly, and let stand at cool room temperature until thick and firm, at least 2 hours, or up to 1 week.
5. Transfer marshmallow base to the bowl of a stand mixer fitted with the whisk attachment. Whipping on medium speed, begin adding the butter 1 tablespoon at a time, waiting for about 5 seconds after each addition. The fluffy creme will cling to the whisk at first but loosen as the butter is incorporated. Once combined, scrape the bowl with a flexible spatula and whip a minute more. The buttercream should be light and creamy but thick enough to hang upside down from a spoon. If it seems stiff or dense (feeling greasy rather than melting on your tongue), scoop a cup into a small bowl and microwave until completely melted, about 30 seconds. Return the melted buttercream to the bowl and whip 15 seconds on medium-high. Conversely, if it seems loose or gooey, refrigerate the entire bowl 15 minutes, then whip 3 minutes on medium-high.