Caramelized Onion, Bacon and Kale Strata Recipe

In a large skillet, cook bacon over medium-low heat until crisp, stirring occasionally. Remove with a slotted spoon; drain on paper towels. Discard drippings, reserving 2 tablespoons in pan. Add onions to drippings; cook and stir over medium-high heat 2-4 minutes or until softened. Reduce heat to medium-low; cook 20-30 minutes or until deep golden brown, stirring occasionally. In a large bowl, whisk eggs, milk, melted butter, mustard, salt and pepper until blended. Stir in bread, kale, cheeses, caramelized onions and bacon. Transfer to a greased 8-in. square baking dish. Refrigerate, covered, 1 hour or overnight. Preheat oven to 325 °. Remove strata from refrigerator while oven heats. Bake, uncovered, 40-45 minutes or until a knife inserted near the center comes out clean. Let stand 10 minutes before serving.