Preheat your oven to 375°F (190°C). Lightly grease a 9×13-inch baking dish with olive oil or non-stick spray.
In a skillet over medium-high heat, cook the diced bacon until crispy (6-8 minutes). Drain on paper towels, leaving the bacon fat in the skillet.
Sauté the chopped onion in the bacon fat for 5 minutes until softened. Add minced garlic and cook for 1 minute. Set aside.
Season chicken breasts with salt and pepper. Sear in the skillet with a little olive oil, 3 minutes per side. Remove and set aside.
In the skillet, combine heavy cream and chicken broth. Whisk in thyme and paprika. Simmer for 2-3 minutes until slightly thickened.
Layer half of the potatoes in the prepared dish, seasoning with salt and pepper. Add asparagus, half the bacon, and chicken. Pour the cream sauce over and add remaining potatoes and bacon.
Top with shredded cheddar cheese. Cover with foil and bake for 25-30 minutes. Remove foil and bake for another 15-20 minutes until golden and tender.
Let the casserole rest for 5 minutes before serving. Slice and serve hot.