Lemony White Bean Dip

Name: Lemony White Bean Dip
Ingredients: 1 1/2 ounces Parmesan cheese, finely grated on a microplane (about 1 1/2 cups); 1/4 cup extra-virgin olive oil, plus more for serving; 4 ounces feta cheese in brine, crumbled, plus 2 tablespoons brine, divided; 1 teaspoon lemon zest, plus more for garnish; 2 tablespoons fresh lemon juice; 1 garlic clove, grated; 1/2 teaspoon kosher salt; 1/4 teaspoon black pepper, plus more for garnish; 2 (15-ounce) cans cannellini beans, drained and rinsed, divided (about 3 cups); 2 tablespoons chopped fresh dill, plus more for garnish; Crostini, for serving