Add the pearled couscous to a pot with 1 tsp of olive oil and toast it on medium heat for 2 minutes. Add in a pinch of salt and pour in the water. Cover the pot and bring it to a boil. Once boiling, reduce to simmer and cook for 12-15 minutes, or until all of the water is absorbed. Set aside then fluff with a fork.
While that cooks, prepare the salad dressing by whisking together all of the ingredients until smooth.
Add the greens, cannellini beans, tomatoes and mozzarella to a salad bowl with the pearl couscous and toss together with the dressing.