Follow the directions here to make the meringue mushrooms and logs.

This step can be done now; or while the cake roll is already prepared and is being refrigerated; or up to 2-3 days in advance.

Store prepared meringue decorations at room temperature until needed.

Prep: Preheat oven to 350F degrees with the baking rack in the middle. Line a large 15 in x 21 in a baking sheet pan with parchment or a silicone mat, set aside (alternatively butter and flour the sheet pan).

Whip 1st mixture: In a bowl of a stand mixer whip together 2 eggs, 1/2 cup sugar, and 1/4 tsp salt until the whipped eggs fall in a ribbon that doesn't disappear for about 2-3 seconds; about 10 minutes.

Whisk 2nd mixture: Meanwhile, in a medium bowl whisk together 1/2 cup sour cream, 1/2 can dulce de leche and 1/2 tsp of baking soda until no lumps of dulce de leche are seen.

Fold the two prepared mixtures together, being careful not to deflate the batter.

Add dry ingredients: Sift in 1 cup of flour and 2 teaspoons of baking powder,  into the wet ingredients and fold the batter until fully incorporated. Do not overmix or the cakes will be tough.

Bake the cake: Pour the caramel cake batter out into the prepared baking sheet pan and spread the batter into an even layer. Bake for about 9 minutes or until the top is lightly golden and springs back when touched. Remove from the oven and completely cool.

Make the syrup: Combine the evaporated milk and the dulce de leche with a whisk or an immersion blender until smooth. Pour into a squirt bottle if available. Set aside.

Skip this step, if using store-bought whipped topping (Cool Whip). 

Whip cream: If using heavy whipped cream, whip the cream with a mixer until medium-stiff peaks. Transfer to a different bowl and refrigerate until the next step is complete.

Make the cream: In a mixer whip 4 oz cubed room temperature butter and 4 oz cubed cream cheese for about 4-5 minutes or until the mixture is very fluffy. Scrape down the sides of the bowl as needed.

Add the dulce de leche in 2 additions and whip to incorporate after each.

Fold the prepared whipped cream (from step 1) or whipped topping in halves.

(skip this step if using pre-roasted hazelnuts)

Preheat oven to 325 with the baking rack centered.

Roast hazelnuts: Place the hazelnuts onto a rimmed baking sheet and bake tossing, every 3-4 minutes and tasting to see if they're roasted to your liking, ~15 minutes,

Cool: Remove from the oven and allow to cool completely.

Remove the skins: Add the nuts to a ziplock bag and keep shaking and rubbing the nuts between the palms of your hands until the skin is removed.

Remove the nuts: The skins will fall to the bottom of the bag, the nuts will be on top. Remove the nuts to a separate bowl, discarding the skins.

Chop the nuts with a sharp knife to the desired size, or add them to a ziplock bag and crush them with a rolling pin. Set aside.

Set cake on plastic wrap: Flip the cake upside down onto plastic wrap that's wider than the cake all around by about 3 inches. Peel off the parchment paper or the silicone mat.

Soak with syrup: Using a squeeze bottle or a spoon, pour the Caramel Soaking Syrup evenly all over the cake layer.

Fill with cream:

Reserve about 1 cup of cream, cover, and refrigerate until later.

Spread the rest of the cream evenly over the cake and sprinkle the hazelnuts.

Roll the cake roll tightly, starting with the shorter side of the roll. Wrap with the plastic wrap and twist the ends. Transfer to a plate and refrigerate.

The cake needs to be refrigerated to set the roll and make it easy to move as you decorate. You can do this for a minimum of 1 hour, or even overnight. The longer, the better.

If you didn't make the meringue decorations earlier, this is also a good time to make the meringue decorations.

Do this step right before removing the cake roll from the fridge for decorating.

Make ganache: Boil 1/2 cup of cream in the microwave. Add 1/2 cup of chopped chocolates or semi-sweet chocolate chips to a cup. Pour the boiling hot cream over the chocolate chips and allow to sit for 1-2 minutes. Stir until smooth.

Cover the yule log with cream and chocolte: Remove the cake roll from the fridge. Unwrap the plastic wrap. Set the cake roll on a wire rack. Spread the reserved 1 cup of cream over the top of the roll leaving about 1 tablespoon of cream for later.

Pour the prepared ganache from the step above over the yule log and spread all over the roll using a spatula.

Optional: To make the tree log design on top use the fork tines to gently go over the chocolate in a wave pattern.

Using a sharp knife even out both ends of the yule log by slicing off a thin slice.

Trim: With a sharp knife trim about 1/5th of the yule log making a diagonal cut. Transfer this piece diagonal cut side towards the side of the yule log.

Add meringue decor: add the meringue logs to the top of the yule log and the meringue mushrooms around it. Use leftovers of the cream or chocolate ganache as glue to secure to the serving platter or the yule log.

Refrigerate until ready to serve.