Chop up your chicken breast into 1/2 inch cubes, sprinkle with about a teaspoon of salt, and set aside.
Chop up your shelled shrimps into 1/2 inch bits (unless you couldn't get the big ones like I suggested) and set aside.
Chop up your onions finely. Do the same with the garlic, watercress and red chili. If you want more heat, leave the seeds on the chili. If not, remove them (the seeds).
Ground up the peanuts in a mortar and set aside.
Heat a wok (it's what I use) with a dollop (I've never measured it... 5 tablespoons?) of your choice of oil.
When the oil starts to pop, reduce the heat, fry the chili pepper and set aside. If you leave the seeds on, fry for no more than a minute or so. Pepper seeds burn quickly. If you choose to remove the seeds, watch for them to wrinkle a bit, drain excess oil, then remove. Again, set aside.
Repeat with the garlic , then the onions till they turn a light golden, slightly crispy brown.
PLEASE NOTE: you must fry the ingredients one by one, NOT mixed together, otherwise you get a weird, almost toothpaste like aftertaste. Of course, if you like that, then go ahead by all means.
I like to set each fried ingredient on separate plates lined with paper towels to absorb the extra oil.
DO NOT FRY THE WATERCRESS AND SHALLOTS. You want them fresh, unspoiled, positively virginal... umm, ok, back to the recipe:
Use the remaining oil to fry your chicken, then the shrimps (again separately). Actually, most prefer to steam the shrimps, or steam them first, THEN fry them, but obviously some people have nothing better to do with their lives. Just fry the damn things is my advice... fewer things to wash up when you're done.
In a large serving bowl, mix lemon juice, salt and sugar, stirring till the sugar dissolves.
Add the chili peppers, garlic, peanuts and onions. Stir.
Plunk in your chicken and shrimps (together is fine). Mix.
Toss in the remaining ingredients, saving the mint and coriander leaves and chopped shallots for last, which you will use as garnishing on top.