This is a fairly basic salsa recipe. You can adjust the amount of jalapenos and cilantro according to how much heat you want from it, as well as adding more or less pineapple to alter the sweetness of it.
1 small yellow onion, roughly chopped
1 clove of garlic, roughly chopped
4 large tomatoes, roughly chopped and seeded as well as possible
1-2 jalapeno peppers chopped and seeded (can remove membrane for milder salsa)
5 sprigs of cilantro leaves, roughly chopped
The juice of 1 lime (make sure no seeds slip through)
1/2 teaspoon apple cider vinegar
1/2 cup of pineapple chunks
Salt to taste
Combine all ingredients in food processor or blender. Pulse blender 3-4 times. Refrigerate 2 hours.