For the tinted coconut: Place the coconut in a mason jar or zip-top bag. Add 3 to 5 drops of food coloring, one drop at a time. Shake until it is completely covered and the desired color is evenly distributed.
For the cupcakes: Position an oven rack in the lower third of the oven and preheat the oven to 350°F. Line 18 cupcake cups with paper liners.
In the bowl of a stand mixer fitted with the paddle attachment, combine the 2 cups sugar, flour, baking soda and sea salt. Let the mixer run on low for 2 to 3 minutes to incorporate air without sifting.
Meanwhile, place the chocolate in a medium bowl, and pour the hot coffee and 1 1/2 teaspoon vanilla extract over the chocolate. Let the chocolate and coffee mixture stand for about 2 minutes to melt the chocolate, then stir until smooth. Set aside.
In another medium bowl, whisk the oil and eggs together quickly so that they combine thoroughly. They will be thick and satiny, and light in color. Whisk in the sour cream but leave some visible streaks of white, being careful not to over mix. Pour in the melted chocolate mixture and mix until just combined. Add the chocolate and sour cream mixture to the dry ingredients in the mixing bowl fitted with the paddle attachment and mix on medium speed adding in thirds until just combined, 1 to 2 minutes.
Remove the bowl from the mixer and incorporate with a rubber spatula any ingredients that may be hiding at the bottom of the bowl. The batter will be very wet and chocolaty, so it helps to transfer the batter into a liquid measuring cup to make it easier to pour.
Pour the batter into the prepared cupcake pan, filling each baking cup about two-thirds full. Refill the measuring cup as needed and repeat until all of the cupcake cups are filled. Bake the cupcakes until a cake tester inserted in the center comes out clean, 20 to 25 minutes. Set aside to cool for at least 20 minutes. Once the cupcakes are cooled, remove them from the paper liners.
For the creamy coconut buttercream frosting: Combine the flour, 1/2 cup of the milk and 2 teaspoons vanilla extract in a small saucepan, and whisk until incorporated. Over medium heat, gradually add the remaining 1 1/2 cups milk and whisk constantly. Continue to cook the mixture until it comes to a low boil. Reduce the heat to low and continue to whisk until the mixture begins to thicken and starts to burp, 2 to 3 minutes
Remove the mixture from the heat and transfer it to a small heat-proof bowl to cool. Stir the mixture occasionally as it continues to cool to keep it lump free. If you do get few lumps, don't worry, you can whisk the mixture to dissolve the lumps, or pass the mixture through a mesh sieve to get a completely smooth consistency. Set the mixture aside to cool to room temperature.
In a stand mixer or with an electric mixer fitted with the whisk attachment, whip the butter on medium speed until it is soft and creamy, 2 to 3 minutes. Gradually add in 2 cups sugar and beat on high speed until light and fluffy, 5 to 7 minutes. Gradually add in the cooled milk mixture and increase the mixer to medium-high speed and whip until the frosting is light and fluffy, scraping down the bottom and sides of the bowl with a rubber spatula to make sure the frosting is thoroughly mixed. The frosting can be stored in an airtight container at room temperature for up to 2 days
To assemble the cupcakes: Use an apple corer or a paring knife to scoop out a hole in the middle of the cupcake about 1 inch deep. (The extra cake is yours for the snacking.) Fill a pastry bag fitted with a 1/2-inch pastry tip with the buttercream frosting and fill the hole of each cupcake with frosting. Frost the cupcakes all over with the frosting. Place the coconut in a small bowl. Roll the frosted cupcakes in the tinted coconut and decorate with Crystallized Flowers, if desired. Store the cupcakes in an airtight container for up to 2 days.
Dilute the meringue powder with 4 tablespoons warm water.
Pick some pesticide free, fresh, fully opened edible flowers such as Johnny-jump-ups, pansies, violets, marigolds and roses. Gently give the flowers a water bath in a small bowl of water with a pinch of salt. Next, dunk them in a bowl filled with ice cubes to perk the petals up. Gently remove the flowers and set aside to air dry on paper towels.
Working over a small bowl, apply a thin layer of the meringue powder mixture with the paint brush. Sprinkle the sugar over the flowers shaking off the excess. Use the tweezers to make sure the delicate flower is completely covered with sugar. Set aside to dry in a cool dry place for 2 to 4 hours. The flowers will take a bit longer to dry in humid weather. Store the dry flowers in an airtight container for up to 6 months.