Avocado in Hamburger ?
There is nothing better than avocado on hamburgers. It BELONGS there. Slice one up and put it on there, you won't regret it. And it pairs up with ketchup or mustard or whatever condiments you put on there wonderfully.
Honestly, avocado belongs EVERYWHERE. It's the food of the gods. Avocado toast is seriously the best, and all it takes is an avocado, a piece of bread, and a toaster. You can put some salt on top of it too if you'd like. And the best part of all this is that avocados are really good for you. I think one of the earlier chapters of this manga had some advice on picking a good one when you go shopping. It can be easy to choose an overripe one if you're careless. You can also just watch some cooking videos on youtube and they'll probably give some tips on that.
Protip: if you're only using half of the avocado, leave the pit in the half you're saving, it will keep it fresh longer.