Directions

1. Pour 1 can of evaporated milk (1.5 cups) into ice cube trays and freeze over night. Evaporated milk is made by removing water from fresh milk and  heating it, so its flavor is more concentrated than fresh milk. If you don't have it on hand, you can use fresh milk as a replacement.
   
2. The next day, bring 1.5 liters of water to a boil and add the tapioca pearls. Switch the heat to medium and let them cook without the lid for 10 minutes. During which, stir gently once every 3 minutes to prevent the pearls from sticking to the bottom.
   
3. After 10 minutes, the sago becomes translucent but still has a white hard center, which looks a lot like caviar. Put on the lid and let the pearls sit in the hot water for 15 minutes. The rest of the heat will continue to cook them until done.
   
4. While waiting, take the flesh out of a grapefruit. Use a pairing knife to score the grapefruit skin across the middle. Then, stick a chopstick underneath and wiggle it around to lose the peel. Do the same thing to the other side. If you don't have chopsticks, use a spoon. This way, you will be able to remove the peel and separate the segments without cutting into the flesh.
   
5. Carefully peel off the translucent membrane and take the grapefruit meat out. Tear the meat into small shreds; try not to squeeze the pulp if possible. In China, you are supposed to use red pomelo, which is bigger and sweeter than grapefruit, but I couldn't find it around where I live, so I use grapefruit as a replacement. Set the pulp aside.
   
6. Cut out 3 ripe mangos. Slice the mango down slightly off the center on both sides. Use a pairing knife to score the flesh, but don't cut through the skin.
   
7. Take a spoon and scoop the mango meat out. Oh, by the way. Make sure the dice are not too big because this is supposed to be a drinkable dessert that you will serve with a thick straw. You want the mango pieces to be able to go through the straw.
   
8. There is still some flesh attached to the seed. Don't waste it. Remove the skin first, cut of the meat as much as you can, then use a spoon to scrape the last little bit.
   
9. I used three mangos, and I got about 600g of meat. Set it aside.
   
10. By now, the tapioca pearls should be done soaking. You can see that the white center in the tapioca pearls is disappeared. That is perfect. Drain the pearls and transfer them into an ice bath to firm up the texture.
    
11. Take the frozen evaporated milk out of the freezer and pop it into a big blender. Add 1/2 of the mango flesh, 3 Tbsps of sugar, and 1/4 cup into the blender (reserve 3/4 cup for later)
    
12. Use the on-and-off mold to blend until smooth. You may need a spatula to help the blender a little bit. Please be careful and don't stick the spatula too deep.
    
13. Drain the tapioca pearls and set them aside.
    
14. To assemble the dessert, add some diced mango to the bottom of a cup; follow up with a layer of shredded grapefruit and a layer of tapioca pearls; then pour in 1/4 cup of coconut milk and fill the rest of the space with the mango milk blend; finally, top with some extra mango and grapefruit. Garnish with mint leaves. This recipe is enough to make three servings, so you should roughly divide all the ingredients into three portions but do not need to measure them precisely. Just go with your feelings.
    
15. You can drink this dessert with a thick straw. If you don't have one, serve it in a bowl and enjoy it with a spoon.