Preheat oven to 350ºF. Line a 12-count muffin pan with cupcake liners.

In a mixing bowl, whisk the flour, baking powder, baking soda, and salt together until combined; set aside.

In the bowl of a stand mixer fitted with a paddle attachment, beat the butter and sugar together on medium speed until lightened and creamy. Beat in the eggs, one at a time, until combined, scraping down the sides and bottom of the bowl as needed. Beat in the Greek yogurt, and vanilla on medium speed.

Pour the dry ingredients into the wet ingredients and mix until combined. Add the buttermilk and mix until just combined, scraping down the sides and bottom of the bowl as needed.

Fill cupcake liners 2/3 of the way full. Bake for 18-21 minutes or until a toothpick inserted in the center comes out clean. Allow to cool in the pan for 5 minutes before transferring to a wire rack to cool completely.

Spread coconut evenly onto a rimmed baking sheet. Bake in a 350ºF oven, stirring occasionally, for about 7-10 minutes or until golden brown. Remove immediately from oven and allow to cool completely while you work on the caramel.

Combine the sugar and water in a medium saucepan set over medium heat. Stir occasionally with a fork until mixture comes to a boil, about 3-4 minutes. Continue to simmer until mixture becomes a medium amber color, about 5-6 minutes, swirling pan every so often. Immediately add the cream, and reduce the heat to medium-low.

Using a heat-resistant spatula, constantly stir the caramel until temperature reaches 225ºF-230ºF, about 4-5 minutes. Turn the heat off, stir in the vanilla, and allow to cool/thicken for about 5 minutes.

Place cooled toasted coconut into a mixing bowl. Add 1 cup of the caramel, stirring until combined; set aside.

Combine the egg whites, sugar and salt in the bowl of a stand mixer, and place the bowl over a simmering pot of water. Whisking constantly, heat mixture until sugar is dissolved and the temperature registers 150-160°F on a candy thermometer, about 3-4 minutes.

Secure whisk attachment onto stand mixer, and beat the egg white mixture on high speed until fluffy and cooled to room temperature. Add the butter, one piece at a time, until smooth and creamy. If the mixture looks curdled, that’s totally normal–just keep beating until it becomes smooth and satiny.**

Add 5 Tablespoons of the cooled caramel; beat until fully incorporated. Transfer buttercream to a piping bag, fitted with a large round tip.

Place the chocolate in a medium bowl. Pour the heavy cream into a glass measuring cup, and heat in the microwave until it just begins to boil. Pour hot cream over the chocolate, cover with plastic wrap, and allow it to sit for a few minutes.

Remove the plastic wrap and stir until smooth. Allow to cool for 10 minutes, then transfer to a pastry bag with the tip cut off.***

Pipe buttercream on top of cupcake, leaving a little well in the center for the topping. Scoop coconut caramel topping on top of the buttercream, then drizzle with the ganache. Repeat with the remaining cupcakes.

Store cupcakes in an airtight container at room temperature for up to 5 days.