This is an emoji/engorji tip.
If you put 3 or fewer emojis on a line by themselves the forum will turn them in to engorji. However, if you put 4 or more in then it keeps them regular emoji sized.
But… You can trick it by using something like the hairspace code so you can do a line of big ones. 
(very useful in Emoji Charades)
So, 3 big cakes
4 small cakes
And then you’d need to do this for 4 big cakes:
🎂🎂<hairsp>🎂🎂