Preheat oven to 350 degrees Fahrenheit. Toss unpeeled garlic cloves with olive oil and salt. Wrap in a piece of aluminum foil. Bake until tender and soft, about 20-25 minutes. Remove from oven and let cool.

In a large bowl, combine lettuce, rice, cabbage, croutons, and cucumber.

In a small bowl, whisk together mayonnaise, water, vinegar, salt, and sugar. Squeeze the skin of each garlic clove so the pulp oozes out. Whisk into the dressing until smooth. Pour the dressing over the salad. Toss and serve.