Every summer we make a big batch of sauce (salsa) that we later use during the year, because we refrigerate it. It's really simple and basic, it does take a couple of hours but trust me, it's absolutely delicious. You have to use ripe tomatoes which you have to peel (there's various ways on how to do that). Then you chop some onions and garlic and throw these two ingredients in a big pot to caramelize a little bit in some olive oil (be cautious not to brown them too much!). Later you add the tomatoes which you preferably diced into little cubes with some water and then let it cook on low heat. After about an hour, when the tomatoes have softened, add a generous dose of oregano or basil or whatever Mediterranean herb you have at your disposal (I usually use thyme and rosemary, since they grow in my garden) + some salt and pepper to taste and let it cook for another hour. Stir a couple of times while it cooks and that's it! A delicious, simple and healthy sauce that you can enjoy with various dishes.