Mix all the ingredients other than the shrimp together in a bowl. Add the shrimp and place in the refrigerator to marinate overnight.
1 small onion, ½ cup olive oil, 1 tablespoon lemon zest, 3 cloves garlic, ½ cup lemon juice, 2 small red chillies, 1 tablespoon grated ginger, 1 teaspoon turmeric, 20-24 raw shrimp