Ingredients
Grilled Onion Blue Cheese Dressing:
1 sweet white onion
2 tablespoons extra-virgin olive oil
Salt and freshly ground black pepper
2 cups mayonnaise
1 cup sour cream
1 cup buttermilk
2 teaspoons hot sauce (recommended: Tabasco)
1/2 teaspoon Worcestershire sauce
12 ounces blue cheese, crumbled

Preparation
Preheat a grill or grill pan. Onions can be grilled utilizing a stove top grill pan or outside grill.
Remove outer skin of the onion. Cut into 1/2-inch thick circles. Place in bowl and season with extra-virgin olive oil, salt, and pepper, to taste. Transfer onion to grill or grill pan and cook over medium-high heat until they have a transparent, caramelized color, about 5 to 7 minutes. Remove from heat and allow to cool, then cut into medium dice.In mixing bowl, combine mayonnaise, sour cream, buttermilk, hot sauce, and Worcestershire until well blended. Add blue cheese and mix well to incorporate throughout dressing. Fold in diced grilled onions. Check for seasoning. Refrigerate until ready to use.3 large hard-boiled eggs, separated and chopped
4 large flour tortillas 1 1/2 cups Grilled Onion Blue Cheese Dressing, recipe follows