Preheat your oven to 350°F and lightly butter a 9x13-inch baking dish. Pour the cream of mushroom soup into a large mixing bowl, then add the milk and sour cream. Whisk everything together until it's smooth—this takes about 1 minute. If you see lumps, don't panic; it thickens up fast once it hits the oven.

Stir in the shredded cheddar cheese, chicken broth, garlic powder, salt, and black pepper. I always taste the mixture at this point and adjust seasonings because everyone's soup tastes slightly different. Add the frozen green beans directly into the bowl (don't thaw them—they'll cook perfectly from frozen). Mix everything until the beans are evenly coated.

Pour the entire mixture into your prepared baking dish. Sprinkle the turkey bacon bits across the top in an even layer—these'll distribute flavor throughout as everything bakes. Now here's the key: reserve about 1/4 cup of the fried onion strings for the last few minutes. Save those for topping at the end so they stay super crispy.

Dot the top with small pieces of butter (tear up those 2 tablespoons into little pieces). This creates pockets of richness as everything bakes together. Slide the dish into your preheated oven for 25 minutes. You'll hear it start to bubble around the edges—that's exactly what you want.

After 25 minutes, pull the dish out carefully (use oven mitts—it's hot). Sprinkle that reserved 1/4 cup of fried onion strings across the top in an even layer. The onions should land on the hot surface and immediately start getting crispy and toasted.

Pop it back in the oven for 3-5 more minutes—just until those onion strings turn golden and smell amazing. Watch it after minute 3 so they don't burn; fried onions go from golden to charred pretty quick. Mine always sits for exactly 4 minutes and comes out perfect.

Let the green bean casserole recipe cool for 2-3 minutes before serving so it sets up slightly. The creamy sauce will thicken as it cools, and you'll get that ideal texture where it's not soupy but still silky. Scoop it into bowls and watch people come back for more.