Lemony Shrimp With White Beans and Couscous

This one is definitely a keeper! So quick to put together and so good!

1 10-ounce box couscous (1 1/2 cups)
kosher salt and black pepper
3 tbsp. unsalted butter - I used olive oil instead
2 cloves garlic, chopped
4 scallions, chopped
1 pound medium shrimp, peeled and deveined
1 15.5-ounce can cannellini beans, rinsed
1/2 cup fresh flat-leaf parsley
2 tbsp. fresh lemon juice

In a saucepan, bring 2 cups water to a boil. Stir in the couscous and 1/4 teaspoon salt. Cover and let sit off heat for 5 minutes; fluff with a fork before serving. Meanwhile, heat 1 tablespoon of the butter (olive oil) in a large skillet over medium-high heat. Add the garlic and scallions and cook for 30 seconds. Add the shrimp and cook, stirring, until they begin to turn pink, about 3 minutes. Stir in the beans, parsley, lemon juice, the remaining butter, 1 teaspoon salt, and 1/4 teaspoon pepper. Cook until heated through, 2 to 3 minutes. Serve with the couscous.