Mussels alla Catalana

Ingredients:

Preparation:

1. Open clean mussels over high heat in a pan. 
2. Drain them and remove a valve. 
3. Pour 2 tablespoons of the filtered cooking liquid into a jar. Add the oil, a little vinegar, salt and pepper. 
4. Close the lid and shake. 
5. Add 1 sliced ​​red onion to the mussels and 500 g of sliced ​​fresh tomatoes. Season with the sauce and mix.