I emailed Mong (my idol) to ask for help regarding my earlier failed cuppies. She thinks my oven temperature could be too high. Looks like I've got to get a thermometer soon if I want to continue my baking journey.
If you haven't seen Mong's work, I suggest you check it out. You'll be amazed at her creativity. Her cuppies are always so delightful to view and inspire me to continue despite the continuous failure. And she's a very humble and helpful lady too!