Crack the eggs into a large bowl and gently whisk until combined. Strain the eggs through a fine mesh sieve to get a smooth mixture.

Add boiling water to the sweetened condensed milk until you have about 1 can’s worth of liquid. Stir well, then pour into the egg and milk mixture (add more boiling water if the whole milk doesn’t fill up to 1 can). Mix everything together until smooth.

Add the sugar to a pot or pan and cook over low heat until it turns an even golden caramel color. Pour the caramel into small ramekins or jars.

Pour the egg and milk mixture into the caramel-lined ramekins. Cover with lids or foil, then steam in a steamer for 20 minutes until set.

Remove the flan from the steamer and let cool. Refrigerate before serving. For extra refreshment, serve with shaved ice if desired.