A fluffy, pipeable vegan buttercream made with refined coconut oil, a splash of avocado or olive oil, powdered sugar, and whipped aquafaba. No vegan butter required. Makes 5 to 6 cups.
1 1/2cupsrefined coconut oilsoftened but not melted (firm and creamy, like soft butter)
3tablespoonsavocado or olive oil
4cupspowdered sugarthe fluffy supermarket kind, not the health food store kind
1 1/2teaspoonspure vanilla extract
1/4teaspoonsalt
Instructions
If using a stand mixer with the whisk attachment:
Whip the aquafaba and cream of tartar in the mixer bowl until it holds medium-stiff peaks, 3 to 5 minutes. Transfer to another bowl and refrigerate until ready to use. Wipe out the mixer bowl and switch to the paddle attachment.
If using a hand mixer:
Whip the aquafaba and cream of tartar in a large bowl until it holds medium peaks, 3 to 5 minutes. Use a big bowl, it climbs. Refrigerate until ready to use.
In a separate bowl (or the wiped-out stand mixer bowl), beat the coconut oil and avocado oil (or olive oil) together for about 2 minutes, until smooth and creamy. Add the powdered sugar a half cup at a time on low, scraping down the bowl with a spatula between additions. Beat in the vanilla and salt.
Add the whipped aquafaba and beat on low until smooth, fluffy, and noticeably lighter in both color and texture. It may feel a little soft or shiny at this stage. That's normal.
Chill the bowl for 15 to 20 minutes, then rewhip briefly until it's stiff and holds a clean peak. That's the right consistency for piping and spreading. Frost at that firmer stage.