The main differences of Vietnamese (milk) Coffee is its use of Vietnamese (coffee) filter and condensed milk. The result is an unforgetable strong and sweet flavor!
A Vietnamese filter is like a small coffee pot where you "cooked" coffee with hot water. It includes a filter/screen (top left), a press (the part with a handle to press coffee, bottom left), a chamber for coffee/hot water (top right) and a lid (bottom right). Very simple and effective! You can find this at any Vietnamese/Chinese market for less than $10.
Sweetened condensed milk is a mixture of whole milk and about 40 to 45 percent sugar, which is heated until about 60 percent of the water evaporates. This sticky-sweet ingredient is often used in baked goods and desserts such as candies, puddings, and pies, as well as a substitute for cream and sugar in coffee drinks (such is the case here! It's also very convenient!).
Put about 1/3 of an inch of condensed milk in the bottom of a coffee cup. The more condensed milk, the sweeter your Vietnamese milk coffee will be. The less condensed milk, the stronger the coffee flavor is.
(NOTE: If you prefer coffee without milk, you may skip step 1, and simply add sugar/ice - optional - to your coffee after it is brewed.)
STEP 2: Assemply all part of the coffee filter, except the press.
Place about three and a half rounded teaspoons of coffee into the device (more coffee, stronger flavor and vice versa). Put the press inside the chamber and turn it until it starts to get snug (not tight).
Place the filter on top of the coffee cup. Pour hot water into the device until it is about 1/4 full. Here's the secret of its strong flavor: just enough boiling hot water, not too much. Your coffee will be as strong as an expresso shot!
Tighten the press (or the water would drip really fast leaving your coffee grind unbrewed), put the lid on and here's the most beautiful part: WAIT. Go chat with someone or maybe twittering for at least 5 minutes (or until you have your desired amount of coffee) then voila! Your coffee is brewed.
STEP 5: Remove the coffee filter, and stir coffee and milk together. The coffee can be served either hot (ca phe sua nong) or cold with ice (ca phe sua da). My personal favorite is having some French bread or pastry with my hot Vietnamese milk coffee. Simply divine!