Gorgonzola and Leek Crème Brûlée

Name: Gorgonzola and Leek Crème Brûlée
Ingredients: 1 tablespoon extra-virgin olive oil; 2 medium-large leeks (about 12 ounces total), split lengthwise, washed thoroughly, and sliced crosswise; 1 small yellow onion, chopped; 5 large egg yolks; 1 cup heavy (whipping) cream; 1 cup half-and-half; 5 ounces Gorgonzola cheese, crumbled; 1 tablespoon minced fresh dill or tarragon, or 3/4 teaspoon dried dill or tarragon; 3 tablespoons minced Italian parsley; Salt and freshly ground black pepper to taste; 24 teaspoons or 6 tablespoons grated Parmesan cheese, or 9 or 6 teaspoons sugar for topping