Into blender (or food processor) put lemon juice, extra virgin olive oil, garlic, tahini and garbanzo. Puree until smooth, stopping occasionally and mixing with rubber spatula as needed.
Add remaining ingredients and blend until smooth, adding water (1 tablespoon at a time) until it has the desired consistency.
Adjust salt and pepper to taste.
Sprinkle pumpkin seeds or sunflower seeds on top and serve.