When making chocolate brownie, wait until it is cool before tipping it out of the tin. And use a rack to tip it onto, not your hand.
You see, I was in a hurry and hadn't connected my brain. I tipped a very warm and soft brownie onto my hand to get it out of the tin and cut it up. Why was I in a hurry? Because I wanted to eat some.
My second best baking hint:
When making chocolate brownie, make a double batch!
Find my chocolate brownie recipe here.