Vanilla Cake With Mango Passion Fruit Jam and Coconut Rum Buttercream

Name: Vanilla Cake With Mango Passion Fruit Jam and Coconut Rum Buttercream
Ingredients: 3/4 cup granulated sugar; 2 1/2 teaspoons pectin powder; 1 cup passion fruit puree (thawed if frozen); 1 cup mango puree (thawed if frozen); 2 sticks plus 2 tablespoons unsalted butter, at room temperature, plus more for the pans; 2 1/4 cups pastry flour, plus more for the pans; 1 1/2 teaspoons baking powder; 1/2 teaspoon salt; 1 cup plus 2 tablespoons milk; 2 teaspoons pure vanilla extract; 2 1/4 cups granulated sugar; 4 large eggs; 1/4 cup coconut rum; 1/4 cup water; 4 sticks unsalted butter, at room temperature; 1/3 cup heavy cream; 2 3/4 teaspoons pure vanilla extract; 3/4 teaspoon salt; 7 cups confectioners’ sugar; 1/2 cup coconut almond butter; 1/2 cup sweetened cereal flakes (such as Frosted Flakes)