Ingredients:
6 large egg yolks room temp (use the 3 extra from the joconde cake plus 2 more)
1 cup maple syrup or honey
1 1/2 cup palm shortening
1 teaspoon vanilla extract
Method:
1. Place the egg yolks in the bowl of a stand mixer fitted with a whisk attachment. Beat the yolk on high speed for about 5 minutes or till thick and light in color. While the yolks are whipping, pour the maple syrup into a saucepan and bring to a boil over medium heat. Continue to boil the syrup till it reaches a temperature of 240F on a candy thermometer, 12 to 15 minutes.
2. Lower the mixer speed and pour the hot syrup into the egg yolks in a slow, steady stream. Try not to hit the beaters or the syrup will splatter all over the bowl. Once all the syrup has been added, beat on high speed till the egg mixture is completely cool. This should take 20 to 30 minutes.
3. Switch to the paddle attachment and add the shortening bit by bit, beating till thick and smooth. Beat in the vanilla. (I used natural food coloring from Whole Foods)
4. If the buttercream becomes loss and liquidy, your egg yolks may not have been sufficiently cooled when you added the shortening. Chill the mixture slightly in the fridge, then resume beating. It will emulsion eventually. If it curdles, the shortening might have been too cold. No worries, just keep beating! Beating the mixture fixes pretty much anything!