Rinse quinoa in a strainer for a few seconds.
Combine 3 cups of the milk and the sugar in a saucepan and bring to a simmer.
Add the quinoa and stir. Reduce heat to medium low and cook for about 30 minutes, stirring every few minutes, especially in the latter part of cooking so your quinoa doesn’t stick.
If mixture starts looking too dry, or you would like a more liquid pudding, add the extra 1/2 cup of milk. I didn’t have too although I must admit I do like a fairly squidgy pudding.
Ladle pudding into bowls, cups, or glasses (as I did here) and top with mango and pineapples.