*For the strawberry puree, simply take 1/2 cup of fresh strawberries plus a squirt of lemon juice and blend in a blender or food processor. Adjust the acid with lemon juice and sweetness with regular sugar. Strain the liquid through a fine mesh sieve into a small container. Store in the fridge for about 3 days.

Wipe down the electric mixing bowl with a paper towel dampened with either white vinegar or lemon juice to remove any dirt or grease. Add the egg whites plus the sugar to the bowl and place over a pot of simmering water. Do not boil! Whisk gently, but constantly, until the sugar has dissolved and the egg whites are hot (160F).

Place the bowl on the mixer with a whisk attachment. Whip on medium-high speed until the eggs change to a glossy and thick meringue. Keep whipping until the bowl's temperature is neutral to the touch, about 10 minutes or more.

Switch to a paddle attachment and add the butter in chunks, one at a time until incorporated, on low speed. Mix until silky and smooth. If it curdles (it did for me!), keep mixing and it will turn smooth again.

Still beating on low speed, add the vanilla and small pinch of salt.

Next, divide the buttercream into thirds- 1/3 in a container for the vanilla, 1/3 in a container for chocolate, and 1/3 in a container for the strawberry flavored frosting. For the strawberry, add 2-3 tablespoons of fresh strawberry puree and a couple of drops of pink food coloring. For the chocolate, melt 5 ounces of bittersweet chocolate and let cool, then add to the reserved buttercream. The vanilla buttercream is left as is.