Step 1

Place the strawberries and sugar in a blender or food processor and process until smooth. Transfer to a pot and bring to a simmer over medium heat. Turn the heat down to low and let simmer for about 10-12 minutes until thickened and syrupy. Using a fine mesh sieve, strain the sauce so it is smooth, pressing out the remaining pulp to extract the juice. You should end up with about 1 cup of strawberry sauce. Allow to fully cool and chill in the fridge.

Step 2

Whisk together the water and sugar in a small saucepan. Turn the heat on low and cover until the sugar is dissolved.

Step 3

Meanwhile add the reduced and cold aquafaba to the bowl of a stand mixer along with the cream of tartar. Whisk by hand with the whisk attachment until slightly frothy, then hook up and turn the mixer on a medium speed.

Step 4

Back to the sugar syrup, remove the lid (using the lid helps any sugar crystals on the side of the pot dissolve into the mixture) and set up a candy thermometer so it isn't touching the bottom of the pot. Watch the temperature carefully until it gets to 234 ºF (112 ºC) then turn up the stand mixer to high so that the aquafaba forms stiff peaks. You can turn up the heat to medium if you are careful and keep a close eye on the temperature.

Step 5

As soon as the sugar syrup reaches 248 ºF (120 ºC) it's ready to be added to the aquafaba meringue. At this point the meringue should have formed stiff peaks, which means that the meringue that clings to the whisk when removed will stay in a thin upright peak when inverted. If you invert the whole bowl over your head it shouldn't slide or budge a centimeter.

Step 6

When the syrup is at the edge of the firm and hard ball stages at 248 ºF and the meringue has reached stiff peaks, keep your mixer on high and slowly drizzle in the sugar syrup in a thin stream. Try to aim between the whisk and the edge of the bowl to keep the sugar syrup from splattering. Be careful as the sugar syrup is VERY hot. Pour the entire syrup into the meringue. The meringue will increase in size as the syrup is added.

Step 7

When all the syrup is added switch to a paddle attachment and turn it on to high. Let the mixture beat until it has fully cooled down. It should feel cool to the touch. You can speed up this process by placing an ice pack underneath the bowl if the shape of your mixer allows.

Step 8

Do not add the fat before the meringue has COMPLETELY cooled down. Once cool, leave the mixer at a high speed and very slowly add in the fat, just a spoonful at a time, letting it incorporate before adding the next spoon. If you do this slowly and all your ingredients are cold everything should work out fine (note: it's normal to lose volume when you add fat, but it thickens up as more fat is added). However, it can happen that the mixture breaks and looks curdled. Do not give up, keep adding the fat and it should come back together. It may need to be chilled if it doesn't come back together after adding the fat, so stick everything (bowl and paddle attachment) into the fridge to chill for several minutes before trying again.

Step 9

When your buttercream is thick and fluffy and all the fat has been added, turn the speed of the mixer down to medium and while running add in the vanilla extract. Then, with the mixer still running, slowly pour in the strawberry sauce. Start with 3/4 cups of sauce and add more to taste and desired color is reached.

Step 10

At this point the buttercream can be used to frost a cake. If you want the frosting to firm up a little before decorating place in the fridge to chill and firm checking every several minutes. Once it's chilled sufficiently take it out and use to frost chilled cakes.

Step 11

If you want to make the buttercream in advance, you can refrigerate or freeze the frosting before the strawberry sauce is added. Bring the frosting to room temperature and re-fluff with the paddle attachment, then add the strawberry sauce and use immediately.

Step 12

See the post for details on decorating.

Step 13

Add the chopped chocolate to a heat proof bowl. Bring the coconut cream to a simmer over medium heat, then pour over the chocolate. Let sit for 1 minute, then whisk from the center out until completely melted and smooth. Add the corn syrup and a pinch of salt and mix just to combine.

Step 14

Let the chocolate sauce cool until it runs easily and thickly off of a spoon, then pour the chocolate sauce into drips along the edge of the frosted and chilled cake using a spoon. Once you've made all your dips pour additional sauce to cover the top of the cake, spreading using an offset spatula and gently tipping the cake. To make a spiral design: let chocolate cool slightly and firm up, then place the tip of the spatula in the center of the cake and spin the cake slowly around while letting the spatula slide outwards as it rotates.

Step 15

Cut the cake when chilled for cleanest cuts, but serve at or close to room temperature for the best textures.