Roast the chillies in a pan and keep them aside

Add a little oil and add the onions, garlic, peppercorns & cloves

Remove when they have some color

Off the tomatoes and allow to char and remove

Add the chillies back in, cover with water and allow to come to the boil and cook for 30 mins

In a food processor, add the chillies, onion, garlic, peppercorns, cloves & tomatoes

Add the Oregano and salt and some of the chilli water and blend to a puree

You may strain the sauce if you wish

Marinate the shrimp with salt, pepper and the chilli powder

Add some oil to the wok and just cook the shrimp on both sides

Add the sauce and cook for a few minutes before serving

Garnish with a pinch of Mexican chilli powder