Salted Maple Buttercream

In the countdown before our departure, we have been cooking and eating our favorite things... with maple syrup topping the list! We are both mad for maple; we like it in baklava, with smoked salmon, in granola, mixed into french toast, even baby back ribs, and we stockpile it compulsively. Last month we set out to make a fall/winter dessert that would showcase this extraordinary elixir at it's finest, and a dark almost bittersweet Blackstrap Molasses and Fresh Ginger Cake with Salted Maple Buttercream was the delicious result. This dessert was a team effort, while I whipped up a spicy molasses cake, Paul boiled down dark amber maple syrup, whipped eggs yolks and butter to a creamy consistency for a transcendent, incredible salted maple buttercream. Paul made Salted Maple Buttercream no less than 4 times in the past month, and while we try to avoid superlatives, I'm pretty sure this is the best flavor of buttercream I have ever tasted. Paul's comment, as he made batch after batch; "remember this one, I want a big bowl of salted maple buttercream for my last meal." 

Yield: approximately 2 1/2 cups 

Ingredients:

• 1 1/2 cups dark maple syrup (use the darkest color/grade you can find) 
• 4 eggs yolks at room temperature (sit whole eggs briefly under warm water before cracking if your eggs are cold)
• 20 tablespoons cold butter, cut into 1 tablespoon chunks
• 1/2 teaspoon kosher salt
• 1/4 teaspoon vanilla

Steps:

1. In a medium saucepan, heat the maple syrup on high until it reaches the softball stage (238 F). The temperature is a way to measure the water content, when the mixture hits this temperature it will have the right water-to-sugar ratio. Watch carefully as this mixture will foam vigorously, and adjust the heat as needed to keep the mixture from boiling over. Reaching 238 F should take 5-10 minutes after it boils. If using a thick bottomed pot, you will not need to whisk or stir this mixture.
2. While the maple syrup is boiling, whisk the egg yolks in a stand mixer on high for 6-8 minutes, (longer if using a hand-mixer). You are looking for the eggs to become very pale, creamy, thick, and quadrupled in volume. 
3. Once the maple syrup reaches the appropriate temperature (238 F), turn the mixer beating the egg yolks to high and slowly pour the hot maple syrup down the side of the mixing bowl into the egg yolks. The mixture will look shiny, light brown and thick. Mix on high until the side of the mixing bowl feels only slightly warm to the touch, approximately 5-6 minutes. This ensures that the maple syrup mixture is cool enough to prevent the butter from melting when added in the next step.
4. Once the egg-maple mixture has cooled sufficiently, turn the mixer speed to medium and add a small handful of butter (2-4 tablespoons).  Allow the butter to dissolve into the mixture before adding a few more chunks of butter. Wait until the chunks disappear before adding more butter, repeating until all the butter is used. The texture will be getting thicker and more satiny as the butter is added. It will take longer for the butter to incorporate with each addition as the mixture cools. Use a spatula to scrape down the sides occasionally.  After you finish the last pieces of butter, the texture should begin to look light and airy.
5. The mixture should be used within a day of making, and will need to come back up to room temperature before spreading (or serving on a cake).  Our favorite combination is serving this on Blackstrap Molasses and Fresh Ginger Cake. 

Note: This is a professional style buttercream, which is more involved than your average frosting. A reliable candy thermometer is essential in this recipe.