Prepare the coconut jam. Combine coconut milk with ¼ cup sugar and pandan leaves in a small saucepot. Bring to a simmer over medium-high heat, keeping the pandan leaves submerged. Simmer for 1 minute then remove from heat and let it sit for 10 minutes. Drain milk, discarding pandan leaves.

Whisk together egg yolks and ½ cup sugar in a medium stainless steel mixing bowl. Slowly add the milk mixture, whisking constantly. Place the bowl over a pot of simmering hot water and cook the custard until it thickens, about 20 minutes, stirring frequently. Remove from heat and strain custard through a fine sieve. Cover and let cool.

Spread coconut jam on half of the bread slices and top with another slice of bread. Melt butter in a nonstick saute pan over medium-low heat. Add the sandwiches and cook until golden brown about 2 minutes. Flip and cook on the other side until golden brown. Remove from heat and cut in half.

Drizzle the soft fried eggs with dark soy sauce. Season with a pinch of white pepper. Serve with kaya toast.