Whenever I yearn for something rather tart and filling, this is one of my favorites. Another mood booster for me, especially when the weather is hot. This will last for 3 days max in the fridge, but in my house, it rarely lasts that long.
Peel and dice 2 large potatoes (about 500 grams). Boil until soft, set aside. When the potatoes are cool enough, add 4-5 tablespoon of mayonnaise, salt and sugar to taste, 2 sprigs of fresh rosemary (or 1 tbsp dried rosemary), add a dash of oregano. Stir well. Put it in the fridge until you're hungry. (or, in my case, eat it right away!)