Separate the eggs. At least 30 minutes before making the cake, take the butter, eggs, and sour cream out of the refrigerator and let them come to room temperature. Measure out the rest of the ingredients.
Position the oven rack to the center position. Preheat the oven to 350° F. Prepare the 9-inch cake baking pan with non-stick spray and parchment paper.
Make the cake
Sift the cake flour, baking powder, and baking soda together. Whisk the salt in, and set aside.
1 ½ cups cake flour, 1 teaspoon baking powder, ¼ teaspoon baking soda, ¼ teaspoon fine grain sea salt
In the bowl of a stand mixer fitted with the paddle attachment, or in a large bowl with a hand mixer, cream together the butter and sugar. Beat on medium speed until light and fluffy, about 5 minutes. Stop the mixer and scrape down the sides and bottom of the bowl halfway through mixing. The mixture should be very pale yellow after mixing.
½ cup unsalted butter, 1 cup granulated sugar
With the mixer running on medium/ low speed, add the vanilla and coconut extracts. Next, slowly add the egg whites while the mixer continues running. Scrape down the sides of the bowl periodically as you slowly incorporate the egg whites.
1 teaspoon vanilla extract, ½ teaspoon coconut extract, 1/3 cup egg whites
Mix the sour cream and coconut milk together in a small bowl. Alternate adding the dry ingredients into the bowl in three additions with the milk/sour cream mixture in two additions, starting and ending with the dry ingredients. Mix on medium speed between additions until fully incorporated.
¼ cup + 2 tablespoons sour cream, ¼ cup + 2 tablespoons full fat canned coconut milk
Transfer the batter into the prepared cake pan. Bake at 350° F for about 22-26 minutes. Carefully take the cake out of the oven when the cake is firm but springs back when gently pressed in on the center, or when a cake tester comes out clean.
Cool the cake in the pan completely on a cooling rack before turning out of the pan, removing the parchment paper, and frosting.
Make the frosting
Use a stand mixer with the whisk attachment or a hand-held mixer to whip the cream on high speed until you achieve stiff peaks. Transfer the whipped cream to a bowl and set aside.
1 cup heavy cream
Replace the whisk attachment with the paddle attachment on the stand mixer (you don’t need to clean the bowl). Mix the cream cheese on medium speed until smooth, about 2-3 minutes. Add the sugar and salt beat on high for 2-3 minutes. Turn the mixer down to low and add the red food coloring if using.
8 ounce cream cheese , ½ cup granulated sugar, Pinch kosher salt, 2 drops red food coloring
Place the guava paste in a microwave safe bowl and microwave 30 seconds to a minute to soften and melt the paste.
½ cup guava paste
Add the softened guava paste in 4 additions, making sure each addition is fully incorporated into the frosting before adding the next, scraping down the sides of the bowl after each addition. Turn the mixer to high and beat for another 1-2 minutes. Using a spatula, gently fold in the whipped cream into the cream cheese mixture.
Frost the cooled cake using an offset spatula. Chill the cake for at least 2 hours before serving. Garnish with shredded coconut.
Notes
Store the cake covered in foil or plastic wrap in the fridge for up to 3 days.The cake can be made into cupcakes if you want. Cupcakes will take about 18-25 minutes to bake, and will make about 12 cupcakes. Don’t forget to line the cupcake pan with paper liners and spray the inside of the liner with cooking spray.