Place the sardines into a slow cooker, add all the other ingredients, close and cook for 10-15 minutes after it reaches boiling point.
The sardines are ready when the water and vinegar have evaporated.
Arrange the rounds of bell pepper on a serving plate, put the sardines on top and moisten with the cooking juices.
Note: Once cooked, the sardines can be stored in a jar filled with olive oil and served later as a salad.
They will keep in the fridge for 3 to 4 days.