If you're making a dish with lots of eggs (custard, quiche), cracking one at a time isn't efficient. Crack two at a time with some smashing and bashing.
Photo by Vicky Wasik
We've covered how to crack an egg with one hand, but over at food blog Serious Eats they have added another cracking tip. Take an egg in each hand and crack them on the side of the bowl at the same time.
It takes some getting used to. If you crack too hard, you'll get eggshell in the bowl (we've got a fix for that, though). A sharp focused tap is what you need to get the job done.
How to Crack Eggs Like a Badass [Serious Eats]