Prawn vindaloo

I tried this dish when I was in Goa and I loved it a loooot. :) I found lots of recipes on internet and I did a mix of all the recipes. It did taste good, but it wasn't the same, so I'll have to try more variations to find the right one.

Ingredients:

Mixture of spices:
vinegar (1-2 tablespoons)
salt (1 teaspoon)
black pepper (1 teaspoon)
red pepper (1 teaspoon)
coriander powder (1 teaspoon)
cumin seeds (1/2 teaspoon)
mustard (1/2 teaspoon)
cinnamon (1/2 teaspoon)
ginger powder (1/2 teaspoon)
cardamon (1/2 teaspoon)
cloves (1/4 teaspoon)

prawns (500 gr)
boiled potatoes (225 gr)
tomatoes (225 gr)
onion (1)
garlic (2 cloves)
oil (2 tablespoons)
lemon juice (1 tablespoon)

Mix all the spices with vinegar. Heat the oil in a pan and fry the onion and garlic. Add the spices. Mix, then add tomatoes and potatoes. Cook 15 minutes on low heat, then add the prawns and cook for a few more minutes. Add the lemon juice and serve with some rice or chapati.