Kentucky Hot Brown Casserole

This Kentucky Hot Brown Casserole transforms the iconic Louisville sandwich into a show-stopping dish that’ll have everyone asking for seconds. With slow-cooked herb-infused turkey, crispy bacon, and a rich Parmesan sauce, this casserole brings all the flavors of the famous Brown Hotel original to your dinner table—without requiring a reservation.

What makes this casserole truly special is how it balances creamy, savory, and crunchy elements in every bite. The herb-butter turkey breast slow cooks to juicy perfection while you prepare the buttery bread cubes that form the foundation of this decadent dish. Then comes the magic: a velvety Parmesan sauce blankets everything before fresh tomatoes and herbs brighten it all up. It’s like Sunday dinner and brunch favorites had a delicious baby.

Ingredients

For the Turkey:

• 1/2 cup unsalted butter, softened
• 1 tablespoon chopped fresh thyme
• 2 teaspoons finely chopped garlic (from 2 garlic cloves)
• 2 teaspoons chopped fresh rosemary
• 2 teaspoons chopped fresh sage
• 1 teaspoon lemon zest (from 1 lemon)
• 1 tablespoon kosher salt, divided
• 1 1/2 teaspoons black pepper, divided
• 1 (6 lb.) bone-in, skin-on whole turkey breast
• 1/2 cup chicken broth

For the Casserole:

• 12 ounces chopped bacon
• 16 ounces cubed thick-cut white bread slices (such as Texas toast)
• 1/2 cup melted unsalted butter
• 2 3/4 teaspoons kosher salt, divided
• 1 1/2 teaspoons black pepper, divided
• 6 large eggs
• 3 cups whole milk, divided
• 1/2 teaspoon dry mustard
• 6 ounces finely shredded Parmesan cheese, divided
• 2 tablespoons unsalted butter
• 2 tablespoons all-purpose flour
• 1 cup diced fresh tomatoes
• 2 tablespoons chopped fresh flat-leaf parsley

Steps

1. Prepare the turkey herb butter: In a medium bowl, combine 1/2 cup softened butter with 1 tablespoon thyme, 2 teaspoons garlic, 2 teaspoons rosemary, 2 teaspoons sage, 1 teaspoon lemon zest, 2 teaspoons kosher salt, and 1 teaspoon black pepper until thoroughly incorporated. The butter should be completely softened (but not melted) to ensure herbs distribute evenly.
2. Prepare and cook the turkey: Carefully lift the skin of the turkey breast without tearing it and spread the herb butter mixture underneath, covering as much meat as possible. This creates a self-basting effect as the butter melts. Sprinkle the outside with remaining 1 teaspoon salt and 1/2 teaspoon pepper. Pour 1/2 cup chicken broth into a 6-quart slow cooker, then add turkey breast skin-side up. Cover and cook on LOW for 4 1/2 to 5 hours, until an instant-read thermometer inserted into the thickest part registers 165°F (74°C). The slow cooking ensures the meat stays juicy.
3. Process the cooked turkey: Remove turkey from slow cooker and let cool for 5-10 minutes until you can handle it. Carefully remove and discard the skin. Chop the meat into bite-sized pieces (about 1/2-inch cubes) and cover to keep warm. You’ll need 10 ounces for the casserole; reserve the rest for sandwiches or other meals.
4. Prepare the bacon and bread: Preheat oven to 375°F (190°C). In a large skillet over medium heat, cook 12 ounces bacon until crisp, about 12 minutes, turning occasionally. Remove bacon to paper towels but save the drippings! You’ll need 3 tablespoons for the casserole. While bacon cooks, toss 16 ounces cubed bread with 1/2 cup melted butter, 1 teaspoon kosher salt, and 1/2 teaspoon black pepper on a baking sheet. Spread in an even layer and bake until golden and crisp, about 16 minutes. The bread should be toasted but not rock-hard.
5. Assemble the casserole mixture: In a large bowl, whisk together 6 eggs, 2 cups milk, 1 1/2 teaspoons kosher salt, 1/2 teaspoon black pepper, and 1/2 teaspoon dry mustard until completely combined. Stir in 2 ounces Parmesan, 10 ounces chopped turkey, most of the cooked bacon (reserve 1/4 cup for topping), 3 tablespoons bacon drippings, and the toasted bread cubes. Fold gently to avoid breaking up the bread too much.
6. Bake the casserole: Pour mixture into a lightly greased 11 x 7-inch baking dish. Bake at 375°F (190°C) until golden brown on top and set in the center, about 45 minutes. The center should no longer be jiggly when you gently shake the dish. If the top browns too quickly, shield with aluminum foil during the last 10 minutes of baking.
7. Make the Parmesan sauce: While the casserole bakes, prepare the sauce. In a small saucepan over medium heat, whisk together 2 tablespoons butter and 2 tablespoons flour until smooth and bubbling, about 1 minute, to create a roux. Gradually whisk in remaining 1 cup milk, adding about 1/4 cup at a time and whisking until smooth between additions. Cook, whisking constantly, until thickened and just beginning to bubble, about 4 minutes. The sauce should coat the back of a spoon. Remove from heat and whisk in remaining 4 ounces Parmesan, 1/2 teaspoon black pepper, and 1/4 teaspoon kosher salt until cheese is melted and sauce is smooth.
8. Finish and serve: Spoon the hot Parmesan sauce evenly over the baked casserole. Top with 1 cup diced fresh tomatoes, 2 tablespoons chopped parsley, and the reserved 1/4 cup bacon. Serve immediately while hot and bubbly. The contrast between the creamy interior, crunchy top, and fresh tomatoes is what makes this dish special.

Smart Swaps

• Use evaporated skim milk instead of whole milk (same amount) for fewer calories but similar creaminess
• Substitute turkey bacon for regular bacon to reduce fat while maintaining flavor profile
• Try sourdough bread instead of Texas toast for a tangy twist that complements the rich flavors
• Replace half the cheese with smoked Gouda for a deeper flavor dimension

Make It Diabetes-Friendly

• Use whole grain bread instead of white bread to lower the glycemic impact (reduces carbs by approximately 5g per serving)
• Substitute unsweetened almond milk for whole milk (reduces carbs by approximately 12g per serving)
• Use 6 egg whites + 2 whole eggs instead of 6 whole eggs to reduce cholesterol while maintaining structure
• Serve with a side of steamed non-starchy vegetables to help slow glucose absorption
• Portion size matters: limit to 1 cup serving size instead of 1½ cups to reduce carbohydrate load by 33%

Pro Tips

• For maximum flavor, make the herb butter a day ahead and refrigerate to let the flavors meld
• If you don’t have time to slow-cook turkey, use 2 pounds of rotisserie chicken instead
• The casserole can be assembled up to 8 hours ahead and refrigerated before baking – just add 10-15 minutes to the baking time
• For a crispier top, broil for 2 minutes after adding the Parmesan sauce, but watch carefully to prevent burning
• This casserole freezes beautifully for up to 3 months—just thaw overnight in the refrigerator and reheat at 325°F (163°C) until warmed through