Place onions, olive oil and thyme into large skillet and toss a few times to coat onions. Place over medium-low heat. Allow to cook, uncovered, flipping occasionally, until onions begin to caramelize and brown in spots, about 25-30 minutes. Add garlic clove and cook 1 minute more. Remove from heat.
Place cashews, tofu, lemon juice and Worcestershire sauce into bowl of a food processor fitted with an S-blade. Process until completely smooth, stopping to scrape down sides of bowl as needed. Season with salt and pepper and thin with water to desired consistency. Pulse a few times to blend.
Add onion mixture and pulse a few times, just until finely chopped and incorporated into mixture. Transfer to a bowl and serve immediately or chill.
Be sure to soak the cashews prior to preparing this recipe. If you forget to soak your cashews, you can "cheat" by soaking them in boiling hot water for at least 30 minutes.Makes approximately 2 cups of dip. One serving is 2 tbsp.