Preheat oven to 375°F (190°C) and grease a casserole dish.
Heat olive oil in a skillet over medium heat.
Add diced onion and cook until soft.
Stir in minced garlic and cook for about 30 seconds.
Add steak cubes and cook for 3–4 minutes until lightly browned.
Season with smoked paprika, garlic powder, salt, and black pepper.
In a bowl mix cream of mushroom soup and milk until smooth.
Layer sliced potatoes evenly in the casserole dish.
Spread the cooked steak mixture over the potatoes.
Pour the soup mixture evenly over the casserole.
Sprinkle cheddar cheese, mozzarella cheese, and crumbled bacon on top.
Cover with foil and bake for 30 minutes.
Remove foil and bake for another 10–15 minutes until potatoes are tender and cheese is bubbly.
Garnish with chopped parsley before serving.