Homemade iced coffee

I've been into iced coffee lately, so when I went to Hong Kong I got myself this tumbler (one of the very few things I'd bought, if I may add). I'd seen this before in Starbucks stores here, but it wasn't till I started making cold-brewed coffee that I began wanting one.

I almost regretted buying it for HK$90 when I saw a Hong Kong Disneyland tumbler at the airport selling for HK$60, but I do like the simplicity of this one.

Oh, and inside the tumbler is a big serving of the iced Vietnamese coffee I always have whenever I have time to make it.