Pissaladiere Onion Olive and Anchovy Pizza

Name: Pissaladiere (Onion, Olive, and Anchovy Pizza)
Ingredients: 1.25 cups all-purpose flour; 0.5 teaspoon salt; 0.25 cup cold unsalted butter, cut into 1/2-inch pieces; 2 tablespoons olive oil; 2 tablespoons water, or as needed; 3 tablespoons olive oil; 2.5 pounds onions, thinly sliced; 3 cloves garlic, minced; 1 small bay leaf; 1 teaspoon chopped fresh thyme; 1 tablespoon drained capers; salt and ground black pepper to taste; 20 large Niçoise olives, pitted and coarsely chopped; 16 anchovy fillets