Caesared Salmon Salad

Name: Caesared Salmon Salad
Ingredients: 2 large garlic cloves, divided; 3 tablespoons unsalted butter, cut into pieces; 2 tablespoons extra-virgin olive oil; (1-inch-thick) rustic white bread slices, torn into 1- to 2-inch pieces (4 cups); ½ teaspoon plus a pinch of kosher salt, divided; 2 lemons, divided; ¾ cup mayonnaise; 1 ounce Parmesan cheese, grated (about 1/4 cup); 2 teaspoon Dijon mustard; 1 teaspoon anchovy paste (or 3 drained anchovy fillets, mashed into a paste); ½ teaspoon black pepper, divided; 1 (24-ounce, 1-inch-thick) skin-on center-cut salmon fillet; 3 (5-ounce) heads Little Gem lettuce, leaves separated (about 8 cups); Shaved Parmesan cheese, for garnish