Before you start, get all of the ingredients ready. Prepare a large piping bag, fitted with a large round tip, I use a 1/2” diameter tip. Set aside.

Line two baking sheets with parchment paper or silicone mat.

I use a baking mat with the macaron template already in it.

Measure out all of the ingredients.

Sift the powdered sugar and almond flour together. Set it aside.

Place a bowl over a pan with barely simmering water. Add the sugar and egg white powder to the bowl if using. If you’re not using egg white powder simply skip it.

Whisk the sugar and egg white powder so it doesn’t clump up.

Add the egg whites to the bowl and whisk until the sugar is completely melted. It will take a couple of minutes. You can test by touching the mixture between your fingers, and if you feel any sugar granules just keep whisking the mixture over the water bath.

Make sure the bottom of the bowl isn’t touching the simmering water because you don’t want the whites to cook.

Also, don’t overheat the sugar syrup, this may cause issues down the line, such as wrinkly macarons.Transfer the syrup to the bowl of a stand mixer.

With the whisk attachment, start whisking mixture on low for about 30 seconds, then gradually start increasing speed to medium. Whisk on medium for one to two minutes, until the mixture is white and starting to become fluffy. Raise the speed to medium or medium-high and whip for a few minutes until stiff peaks are formed.

When making the black macarons, I added about 3/4 tsp of black powder food coloring to the meringue during the initial whipping stage. This will help later to not have to add so much gel food coloring to obtain the deep black.

If making the white macarons don’t add any food coloring at this point.

To know if the meringue is done whipping , keep your eye on the whites. Once they get glossy and you start seeing streaks formed by the whisk, and the meringue raising in the center of the whisk, it might be time to stop.

You don’t want to overbeat the mixture at this point, because you don’t want to add too much air to it. Just whisk until stiff peaks have formed.

Whisk until stiff peaks have formed. When you pull your whip up, the peak should be stiff and shooting straight up, with possibly a slight bend at the top, but not bending to the side.

Pour the sifted powdered sugar and almond flour into the stiff meringue.

Start folding gently forming a letter J with a spatula.

Add the food coloring at this point, if using. If making the black batter add gel black food coloring, I add a lot of it, sometimes almost half of a small bottle.

To make the white batter I simply omitted the food coloring. You could also add white powder food coloring. It is not needed but it does help keeping the macarons super white.

After adding all the food coloring continue to fold the batter, incorporating the ingredients and then squeezing the air out by pressing the batter down along the sides of the bowl as you stir.

How to know when to stop folding the batter: It’s time to stop folding when the batter is glossy and has a thick and flowing consistency. There are several ways to test this.

First, pick up some batter with the spatula and try to draw a figure 8 with the batter that is dripping off the spatula. If you can form several 8 figures without the batter breaking up, that’s one indication that it might be ready.

There’s another test you can do. I call it the Teaspoon test. Grab a teaspoon of batter and spoon onto the parchment paper or silicon mat. Wait a minute to see how it behaves.

If the batter stays stiff, forming a point and doesn’t spread out, fold a little bit more, about 3 folds.

Test again.

You don’t want your batter to be too runny either. So be careful not to over mix. It’s always best to under mix and test several times until the proper consistency has been achieved.

When you hold the spatula with batter on top of the bowl and the batter falls off the spatula slowly but effortlessly the batter is ready. The batter will keep flowing off the spatula non-stop, but not too quickly.

Once the batter spreads out a bit and starts to look glossy and smooth on top, on the parchment paper, it's ready.

Transfer the batter to the piping bag.

Place the piping bag directly 90 degrees over the center of each macaron template. Apply gentle pressure and carefully pipe for about 3 seconds, and then quickly pull the bag up twisting slightly.

Use a toothpick to pop any air bubbles in the surface of the shells.

Let the trays sit for a while so the shells will dry out a little bit. I usually leave about 20-40 minutes, depending on how humid the day is. You’ll know they’re ready when you gently touch the surface of a macaron and it seems dry.

Bake one tray at a time.

Bake for 5 minutes, rotate the tray.

I bake each tray for about 15 to 20 minutes.

When baked, the macarons will have a deeper color and formed feet. If you try to move a macaron, it shouldn’t feel jiggly. If the macaron is still jiggly, keep baking.

Remove from the oven and bake the other tray.

Let the macarons cool down before proceeding with the filling.

To decorate the shells with the rainbow drizzle, I used candy melts. I did blue, green, red, yellow, orange, and since I couldn’t find purple, I mixed pink and blue candy melts to make the purple color.

Melt the candies in the microwave at 15 second intervals, stirring in between, and stir until completely melted.

Place each color in a piping bag, or use a squeeze bottle.

Pipe one color in each shell, follow by the next color of the rainbow.

Let the shells dry completely.

Raise the speed to medium high and whip for another minute. Add the vanilla and mix to combine.

If the buttercream is too soft, add more powdered sugar, and if the buttercream is too stiff, add a bit more milk or water, one teaspoon at a time, to achieve the perfect consistency.

Once the buttercream is ready, divide it between 6 different bowls.

Color each bowl one color of the rainbow.

I am using powdered food coloring because it’s so much better for buttercream than gel because you don’t add any extra moisture to the frosting.

Lay a piece of plastic wrap on the counter. Then pipe or spread with a spatula each color on the plastic wrap.

Roll the plastic into a log then snip the excess plastic at the bottom with scissors.

Place the log of frosting inside a piping bag fitted with the tip of choice. I am using a Wilton 6B piping tip.

Then pipe a bit of frosting on each bottom macaron shell.

Try to apply even pressure as you pipe so all the colors come out at the same time.

Top with another macaron shell.

Let the macarons mature overnight before serving.

Let them sit at room temperature for about 10 minutes before serving.

These macarons can be stored in the fridge for 5 to 7 days, or in the freezer for up to 1 month or so.