For the Cake:

• Preheat the oven to 350°F (175°C). Grease a 9-inch glass baking pan.

Separate the eggs:

• Place the egg whites in a clean bowl and the yolks in another bowl.
  3 large eggs
• Whip the egg whites (with cream of tartar, if using) using an electric mixer until stiff peaks form. Set aside.
  3 large eggs, 1/4 teaspoon cream of tartar

Prepare the batter:

• In a separate large mixing bowl, beat the egg yolks with sugar until pale and creamy.
  1/2 cup sugar or preferred sweetener
• Add the cottage cheese, vanilla extract, coconut rum, and melted butter. Mix until well combined.
  2 cups cottage cheese, 1 tablespoon coconut rum, 1/4 cup butter, 1 teaspoon vanilla extract
• Gradually fold in the gluten-free flour blend, coconut flour, baking powder, baking soda, and salt until the batter is well-mixed.
  1/2 cup gluten-free flour blend, 1/4 cup coconut flour, 1 teaspoon baking powder, 1/4 teaspoon baking soda, 1/4 teaspoon salt
• Fold in the pineapple and shredded coconut (if using).
  1 1/2 cups fresh pineapple, 1/4 cup unsweetened shredded coconut

Incorporate the egg whites:

• Gently fold the whipped egg whites into the batter in three additions to keep the mixture light and airy.
  3 large eggs

Bake:

• Pour the batter into the greased 9-inch glass pan and smooth the top.
• Bake for 45–55 minutes, or until the cake is golden brown on top, and a toothpick inserted into the center comes out clean.
• Cool the cake in the pan for 10 minutes, then transfer to a wire rack to cool completely.
  

For the Coconut Rum Cream Cheese Frosting:

Whip the cream cheese and butter:

• In a large bowl, beat the softened cream cheese and butter together until smooth and creamy.
  8 oz cream cheese, 1/4 cup butter

Add powdered sugar:

• Gradually add the powdered sugar, beating until the frosting is fluffy and well combined.
  1 1/2 cups powdered sugar

Add coconut rum and vanilla extract:

• Stir in the coconut rum and vanilla extract. If you want a richer texture, add 1–2 tablespoons of coconut cream or heavy cream and beat until smooth.
  2 tablespoons coconut rum, 1-2 tablespoons coconut cream or heavy cream, 1 teaspoon vanilla extract

Optional pineapple addition:

• Fold in 1/4 cup of well-drained crushed pineapple for an extra tropical flavor.
  1/4 cup crushed pineapple

Assembling the Cake:

• Frost the cooled cake generously with the coconut rum cream cheese frosting.
• Garnish with reserved fresh pineapple chunks and a sprinkle of toasted shredded coconut for a decorative touch.