The number of shrimps you will need will vary greatly. I serve this with rice or rice vermicelli and lots of veggies so I count around 6 per person and will usually throw in a few extras for good luck.
Peel the shrimps and chop them in 2 or 3 parts ( the tail part should be cut longer as it’s thinner). Throw them in a bowl. Mince garlic, onion, and ginger throw it all in the bowl.
Put oil in a stainless steel pan and put it on high heat. Once it’s really hot, dump everything in the bowl in the pan and stir for 30-40 seconds. When it looks fully cooked ( no more blue spot on the shrimps) throw soy sauce in the pan and stir for another 15 seconds or so.
You don’t want to overcook the shrimps, they will cook in just a minute at such high heat.