In your cast iron (or other) skillet, fry the bacon on medium heat until done to your liking. Set aside to drain and cool.
Put an inch or so of water in the bottom of your saucepan with a steamer basket, and place eggs in the basket. Turn the heat to medium-high and set a timer for 20 minutes. When the timer goes off, soak the eggs in cold water for a few minutes before peeling. Set aside.
Meanwhile, you can boil some salted water to cook your shell pasta noodles. Bring the water to a boil, drop the noodles in, and cook until tender. Don't overcook them, they are better in the pasta salad if you cook them just until tender - they will get softer as they cool and soak up the dressing. I like to drain the noodles and give them a quick rinse. Set aside.
While your noodles and eggs are cooking, you can mix the dressing and chop the other ingredients. For the dressing, mix the mayonnaise, Greek yogurt, sugar, cider vinegar, salt, and pepper. Slice or dice your red onion, dice your cheddar cheese into small bite-size cubes, and finely chop your broccoli. We use most of the stem in our house too, just chop it in small pieces. My dogs usually get a few chunks too, they like it. Chop or slice your eggs, too.
Once the dressing is mixed up, I like to put the warm noodles in the bowl with it first and stir it up really well. This helps the noodles soak up the dressing. Then, you can gently stir in your onion, broccoli, cheese, boiled eggs, and bacon. (If you like crispy bacon, you can consider leaving the bacon out of the full bowl of salad and just add it at serving time.)