What are your go-to dinner party dishes?

We're having our foodie friends over for dinner on Saturday and I'm doing the cooking... they love to cook and usually have us over, but we want to return the favor. Also, if they come to our house, we can hang out after we put LO to bed.

I need ideas for something delicious, relatively healthy (and low carb, this couple doesn't eat a lot of carbs), and somewhat easy or able to be prepared in advance. LO will still be awake when they first come over and I'm getting the food ready, so I won't have my full attention on cooking!

ETA: One idea I had was to make scallops, so if you have any scallop recipes you recommend, that would be great... however, if a second couple comes over, the wife doesn't eat seafood, so I need other ideas in case they're able to come.