Yellow Cupcakes:

Let 8 tbsp of unsalted butter, 2 large eggs, and 1/4 cup of sour cream come to room temperature.

Place an oven rack in the middle position, and preheat your oven to 350 F (175 C). Prepare a muffin pan with cupcake liners. This recipe will make 12 cupcakes.

In a medium-sized mixing bowl, add in 1 1/2 cups cake flour, 1/2 tsp baking powder, 1/4 tsp baking soda, and 1/4 tsp of table salt. Whisk these dry ingredients together till they're well combined.

In the bowl of your stand mixer, add in the 8 tbsp of room temperature unsalted butter, and beat on medium-high speed for 1 minute till the butter is smooth and creamy. Stop the mixer and add in 3/4 cup of granulated sugar, then continue beating on medium-high for 2 minutes, until the sugar and butter mixture looks fluffy.

While continuing to beat on medium-high, add in the 2 room temperature eggs, 1 egg at a time, waiting for the previous egg to be fully combined before adding the next one. When the eggs are combined, add in the 1/4 cup of room temperature sour cream, 1/2 cup of milk and 2 tsp vanilla extract, just until combined. Stop the mixer and scrape down the bowl as needed.

Turn on to medium-low speed, and slowly add in the dry ingredient’s mixture, and continue beating just until combined. Stop the mixer and scrape down the bowl as needed to make sure everything is combined. Then mix again on medium speed for another 30 seconds to ensure all the dry ingredients are mixed in and the batter is uniform.

Scoop the batter into the cupcake liners, making sure to only fill them 2/3 of the way up. The batter will rise quite a bit, and going above the 2/3 of the way will result in the batter overflowing. To keep the cupcakes from doming makes sure your ingredients are room temperature. Also, when filling the cupcake liners put about a heaping tablespoon and then a quarter of a table spoon into the liner. You want them to be just slightly over half-way full.

Bake these cupcakes in the preheated oven at 350 F (175 C) for 15 to 18 minutes, or until a toothpick inserted in the center comes out clean. Let the cupcakes cool in the molds completely to room temperature before frosting them.

Italian Meringue Buttercream Frosting

Separate 2 eggs into yolks and whites while they are still cold - save the yolks to use for another dish. Let the 2 egg whites come to room temperature. Take 1 cup (2 sticks) of butter and slice them into 1-inch cubes, and let them come to room temperature.

In the bowl of your stand mixer, add in 2 room temperature egg whites and 1/4 tsp of cream of tartar. With the whisk attachment, beat this on medium speed. Slowly add in 1/3 cup of granulated sugar, and continue beating till you see soft peaks forming. Let this rest.

Take a medium sized saucepan and add in 2/3 cup of granulated sugar and 2 tablespoons + 2 teaspoons of water. Heat it over medium-low heat. Wait for the sugar to dissolve completely and the mixture looks clear.

When the sugar has dissolved, attach a candy thermometer and turn up the flame to the highest level possible. Without stirring, continue heating till the sugar-water mixture reaches the softball stage, which is 235 F (110 C). Pay very close attention to the thermometer. If you let the sugar heat pass 235 F, your resulting frosting will be grainy.

As soon as you see the temperature read 235 F (110 C), remove the saucepan from the heat. Turn on the mixer on medium-low speed, and immediately drizzle the hot sugar mixture into the egg-white meringue in a slow steady stream. The sugar should be hot enough to be in the soft-ball stage so it stabilizes the eggs, as well as hot enough to pasteurize the egg whites so they are safe to eat.

When all the hot sugar syrup has been added, continue running the mixer until the mixture cools completely to room temperature, which could take 15 to 20 minutes or so. Do not worry, as you cannot "overmix" this meringue. Letting the mixer run just helps to cool down the meringue faster. It should end up having a nice silky-smooth texture, and it should be the same temperature as the room temperature butter before they are combined.

When the meringue has cooled completely to room temperature (after 15 to 20 minutes of mixing on medium-high, turn the speed down to medium-low. One cube at a time, add in the 1 cup of room temperature butter, waiting for each piece of butter to get incorporated before adding the next one.

If the mixture starts looking curdled, do not worry. It just means the mixture is too cold and it will become smooth once it warms during mixing. Again, buttercream cannot be "over-mixed". If the mixture starts looking soupy, do not panic either. It just means the mixture is too warm (tends to happen when it's a hot day). Just put your bowl in the fridge for 10 - 20 minutes for its mixture to firm up.

Once all the butter has been incorporated, turn the speed back up to medium-high, and add in 1/2 tbsp of vanilla extract an 1/4 tsp of table salt. Continue mixing the buttercream on medium-high speed for another 5 minutes, or until it's well-incorporated, smooth, and has a silky consistency. Do not worry about over-mixing, as you can't really overmix meringue-based buttercreams.

Making the Roses:

Separate the buttercream frosting into two separate bowls. Transfer 1/2 cup which will be using for the matcha green leaves and 1 1/2 cups of frosting which will be used for our pink roses.

From the 1 1/2 cups of separated buttercream, take 1 tbsp and transfer it to a separate microwavable bowl. Add 1 drop of gel food coloring to this 1 tbsp of buttercream (I'm using super red gel food coloring for the roses), and microwave it for 10 seconds. Microwaving this small portion will allow the colors from the food coloring to take to the buttercream, as food coloring does not readily dissolve into buttercream.

Once you have this small portion of buttercream with activated coloring, mix it back into the 1 1/2 cups of buttercream set aside for the roses. Add more or less coloring, 1 drop at a time using that microwaving technique, to achieve the color you want. I'm using only 1 drop here for this, for more natural pale pastel pink roses.

Take a piping bag and attach a number 104 petal tip. Fill the bag with the pink frosting, or whatever color frosting you're making the roses.

I'm using a 2" diameter flower nail. Squeeze a little bit of frosting onto your flower nail. Add a 3" x 3" square piece of parchment or wax paper onto the nail. With the thicker part of your tip facing down closer to the nail, at a slight angle, form a conical shaped base by squeezing the frosting while turning the nail.

Create another smaller cone on top, holding the tip at a slightly sharper angle. Reinforce the bottom cone by going over the base rim with another layer of frosting.

On top of this conical base, create the center of the rose by piping a tight circle with a small opening at the top while turning the nail.

Create the next layer of petals by piping three upside-down U shapes around the center of the rose. Pipe in one direction, while turning the nail in the opposite direction. Start each U shape at the center of the previous U shape.

The next layer will be 4 petals. Use the same technique of piping U shapes, piping in one direction while turning the nail in the opposite direction, starting each petal in the middle of the previous petal.

The final layer will be 5 petals, using the same technique.

When your rose is done, detach the square of parchment paper from the nail, transfer it onto a flat surface, and store your finished roses in the freezer to firm up while working on the remaining roses.

This should make approximately 18 pink roses depending on the size you make them. Store all the roses in the freezer until you're ready to use them.

Arranging the Roses and Piping Green Leaves:

When the roses are firm, take them out of the fridge.

Add a small dollop of pink frosting on the surface of the cupcake where a rose is going to sit. Using scissors or just your hands (but be very careful), one at a time, detach the roses from the square of parchment paper as you arrange them. Place large roses on the center of the cupcakes and any smaller roses you can group together to place on your cupcakes.

In the separated bowl of 1/2 cup of the plain frosting mix in 1 tsp of Matcha powder for a natural green color. The matcha should dissolve in the buttercream so no need to microwave. This will also add a hint of delicious matcha flavor.

Transfer the green frosting into a clean piping bag with a leaf tip. I'm using a number 352.

Wherever there are gaps between the roses, create leaves by holding the tip perpendicular to the orientation of the leaf you want. Then squeezing while jerking back and forth a bit, then releasing, to create texture in the leaves.

Serve cake at room temperature. Store leftovers in the fridge, and let it come to room temperature before serving so the Italian meringue buttercream softens and for a more vibrant caramel flavor. Enjoy!