In a high-speed blender, combine the Caesar dressing ingredients and blend until very smooth. Taste and adjust the seasoning, as needed. (I usually add 1/4 teaspoon more salt; it will be diluted over all of the lettuce!)
Transfer the chopped romaine lettuce to a large serving bowl, and pour some of the dressing over the top. Toss well, and add more dressing, until it's sufficiently coated to your liking. You might not use all of the dressing; it will keep well in the fridge for up to 5 days in the fridge and makes an amazing dip for veggies or pizza. Top with crunchy croutons or roasted chickpeas, then serve right away. It's best if you can store the lettuce and dressing separately if you think you're going to have leftovers; the dressed lettuce will be soggy the next day.
Nutrition information is for 1/6 of this recipe, and includes the lettuce and dressing only. This assumes you'll use roughly 1/4 cup of dressing per serving, and is just an estimate, not a guarantee.This recipe is naturally gluten-free if you use roasted chickpeas as the topping, or gluten-free croutons.