Watercress Pesto with Linguine

Name: Watercress Pesto with Linguine
Prep time: 10 min
Cook time: 15 min
Total time: 25 min
Cuisine: Italian
Ingredients: 1 bunch watercress (1 bunch of watercress); 1 garlic clove (1 garlic clove, ); 4 tablespoons parmesan cheese (4 tablespoons parmesan cheese + shavings); ½ cup pine nuts (½ cup pine nuts); ½ cup olive oil (½ cup olive oil); 1 pound linguine pasta (1 pound linguine pasta); 4 tablespoons heavy cream (4 tablespoons heavy cream); 1 tablespoon butter (1 tablespoon unsalted butter)