Beat the sugar and eggs with a mixer until the sugar dissolves, then add the liquid vanilla, salt, and emulsifier. Mix until thick and forms ribbons.

Add the cake flour, cornstarch, and cocoa powder while sifting. Mix on low speed until just combined. Turn off the mixer and add the melted butter, chocolate paste, and sweetened condensed milk alternately, folding gently until well combined (don't overmix to avoid deflating).

Pour into a greased and lined baking pan (my pan is small). Bake in a preheated oven at medium-low heat until cooked through. Test with a skewer; if it comes out clean, it's done.

NOTE: You can make this in other flavors like pandan. If making pandan or other flavors (not chocolate), replace the 10 grams of cocoa with 10 grams of cake flour. Don't skip the 10 grams.