For the Pickled red onion: Blanch 1 sliced red onion in a small saucepan of boiling water to cover for 1 minute and drain in a colander.
Then return them to the pan and add ½ cup of cider vinegar, a ½ teaspoon of salt, and just enough cold water to barely cover the onions.
Bring to a boil over high heat and simmer the onions 1 minute. Transfer the onions and brine to a glass jar and chill.
Place the lettuce onto a large serving plate, followed by the sliced red cabbage, red onion, grilled sweet pepper and cannellini beans.
Top with shaved parmesan and of course some croutons and sprinkle with dressing. For the dressing: Puree the garlic, vinegar, and anchovies in a blender until smooth.
With the machine running, slowly drizzle in the olive oil. Season with salt and pepper.