Make sure your mixing bowl is completely free of any oil or residue. If you want to go the extra mile, use a paper towel with a little vinegar or lemon juice to wipe the bowl and attachments clean.

Measure everything out before you get started as it will make your life a lot easier.

Prepare your egg whites and make sure there are no shells or yolks. Any yolk in your whites will keep your meringue from stiffening.

Add the egg whites, pinch of salt and cream of tartar. Whisk on high speed until they begin to look frothy. Slow the mixing to medium-high and slowly add 1/3 cup sugar.

Continue to whip your egg whites for several minutes until stiff peaks form.

Turn your mixer to medium or medium/low while you cook your sugar. Do NOT stop the mixer!

Add 1 cup of sugar and 1/3 cup water to a medium saucepan and heat over medium while stirring until the sugar dissolves. Turn the heat to medium-high and stir occasionally until it reaches 235 degrees on an instant thermometer.

Turn the mixer back up to high and slowly drizzle your sugar syrup down the inside of the bowl while continuing to whisk. Be careful not to hit the whisk or you may end up being splattered by hot sugar!

Continue to whisk on high until stiff peaks form again. Then turn the mixer down to medium until the bottom of the bowl cools.

Once the bowl is cool, switch out the whisk for the paddle attachment and add the vanilla then begin adding your room temperature butter one Tablespoon at a time until it is all fully incorporated.

Continue to beat the butter on medium-high speed until the buttercream is smooth and there are no more visible chunks of butter.

You should now be ready to frost!