Add the canned whole tomatoes to the slow cooker. Using a potato masher, crush them into pieces; you'll want to leave some nice chunks of tomato. If you don't have a potato masher you can break the tomatoes apart with clean hands.
Add everything else BUT the fresh herbs and lemon zest.
Cook on HIGH for 4 hours or LOW for 6 hours, stir at least once halfway through cooking.
When done, stir in the fresh parsley, fresh basil, fresh oregano, and lemon zest. Season to taste.
Serve immediately with spaghetti or your favorite pasta, garnish with more fresh parsley or basil. Enjoy!
Notes
If the sauce is too thick, add in hot pasta water ¼ cup at a time until at desired consistency.
Store in the refrigerator for up to 3 days in an airtight container.
Reheat on the stovetop or the microwave.
Black olives or green olives can be used as a substitute for the kalamata olives, or try mixing all three into your sauce.
The anchovies can be left out if desired. Or tuna can be used.