Place onion and garlic in a food processor or chopper to finely chop.
Add chopped onion and garlic mixture, eggplant, zucchini, spices, tomato paste and coconut milk to your slow cooker. Stir everything together. At this point if the mixture seems too thick you can add in a little vegetable broth. Cook on low for 4-5 hours. Garnish with fresh parsley or cilantro. Serve warm with rice and naan.