Directions for the sour cream & Coffee chocolate cake
 

• Preheat the oven to 180C°/350F°. Grease a 37 x 25 cm (15 x 10 – inches) half sheet pan and line with parchment paper.
   
• In a large bowl sift together the all-purpose flour, baking soda, cocoa powder, and a pinch of salt. Set aside for now.
   
• In a small saucepan melt the butter over low-medium heat, once melted remove it from the stove, and set aside until lukewarm.
   
• Into the bowl of an electric mixer fitted with the whisk attachment add the sugar, eggs, and vanilla bean paste ( if using) on high speed, mix until fluffy, thick and lighter in color ( about 10 minutes)
   
• Add the brewed coffee and sour cream to the lukewarm melted butter, and combine with a whisk.
   
• Set the mixer to low, and slowly pour the melted butter mixture into the egg mixture in a thin, steady stream, aiming for the side of the bowl instead of the whisk, continue mixing on low speed until just combined — about 20-30 seconds.
   
• With the mixer on low, ( Mix lightly) add the flour/cocoa mixture with a large, thin-edged spoon, add a spoonful at a time and mix on low just until combined it is very important to mix lightly. — about 20-30 seconds.
   
•  Mix lightly at all times to not knock out the air in the bubbles you made by whisking. When you are done adding all the dry ingredients, stop mixing!!
  at this point, you will still see some of the dry ingredients on the side of the bowl and in the middle.
   
• Remove the bowl with a silicone spatula scrape the bottom and the side of the bowl, gently fold to combine thoroughly.
   
• Pour the cake batter into the prepared baking sheet.
   
• If time permits, let the cake batter steep/rest in the pans for 20 minutes before baking; As this step makes for better cakes, otherwise proceed as directed.
   
• Bake the cakes in the center of the oven for 15 -20 minutes, or until the top of the cakes springs back when gently touched with your fingertip, and a toothpick inserted in the center of the cake comes out clean.

Directions for the chocolate caramel Frosting part 1
 

• Chop the chocolate as fine as possible, the finer you chop the chocolate, the quicker it melts with the caramel warm sauce.
   
• Pour the heavy cream into a medium saucepan add the vanilla bean paste, give it a quick whisk.
   
•  Place over low heat just to keep the heavy cream lukewarm and to infuse the vanilla bean paste into the heavy cream.
   
• Put the white sugar, light corn syrup, and water in a medium saucepan set over medium heat, but do not stir. ( stirring encourages crystallization)
   
• Let the mixture cook until it caramelizes into a golden brown, it happens quickly so keep an eye on it.
   
• You can if needed use a wooden spoon as soon as you see the mixture is getting way too caramelized on the side of the pan,
  just carefully draw the caramelized sugar towards the center of the pan with a wooden spoon, to help the sugar cook evenly.
   
• Once all of the sugar has caramelized to a rich golden brown remove from heat and carefully stir in the lukewarm heavy cream/ vanilla mixture, pour in just a tiny bit at a time, especially at the beginning, and mix to combine.
   Be very careful, as it will bubble up and steam like crazy) add the sea salt and stir.
   
• Cool the hot caramel sauce for 30 seconds,  if the caramel is too hot it could separate or burn the chocolate.
   
• Then quickly pour it over the finely chopped chocolate, wait for two minutes, during this time, the chocolate will soften and begin to melt. After two minutes use a whisk or spatula stir until the chocolate is completely melted.
  Try not to stir too much in the mixture, just until combined.
   
• Leave to cool at room temp for about 30 -40 minutes, in the meantime remove the butter out of the fridge.
  
  
  
  Directions for Chocolate Caramel Frosting part 2
   
• Take the butter out of your fridge about 30 minutes before you whip up this frosting, cut it up into small cubes
   
• In a bowl of an electric mixer fitted with the paddle attachment, add the butter and beat on medium-high speed to soften the butter until it is light and fluffy. ( about 3-5 minutes.)
   
• Make sure to stop the mixer and scrape the sides and the bottom of the bowl with a silicone spatula a few times in between.
   
• Add the cooled caramel/chocolate mixture to the creamed butter and mix on low speed until just combined about 1 to 2 minutes, Make sure to stop the mixer and scrape the sides and the bottom of the bowl with a silicone spatula in between those two minutes.
   
• After 1 to 2 minutes your chocolate Caramel Frosting should look glossy, smooth, and dark in color as shown in the picture above.
   
• If you like the frosting to be lighter in color and more fluffy in consistency mix it on medium-high for about 5 minutes.
   
• You’ll notice your chocolate caramel frosting lightens in color quite a bit as you beat it, but it will darken later on after it sits out a bit.
   
• Remove the bowl from the mixer, mix the frosting by hand for a minute with a silicone spatula this will help to push out all of the air pockets creates by the electric mixer.
   
• Add large dollops of the whipped chocolate caramel frosting onto the cooled chocolate sheet cake, and frost the entire chocolate sheet cake with the frosting using an offset spatula or the back of a large spoon.
   
• The chocolate sheet cake will keep at room temp, covered for up to 2 days, I do not recommend placing it into the fridge as it can harden the frosting and the cake.
  If you prefer to place it in the fridge, allow the cake to stand at room temperature for at least 2 hours before serving.