Don't tell me to freeze stuff in advance. I already forgot.
Soup! I often make soup at the last minute, we always have a few different vegetables in the freezer, and usually frozen wontons. If I'm making wonton soup, I go through the fridge and pantry and pull out all the Asian-style condiments and squirt a little of each into the pot, along with some "better than bullion" paste, and water.
Another thing that I often throw together at the last minute is frittata. It's a great way to use up any veggies that are looking a little wrinkly, whisk up a few eggs, add any cheese and seasonings you like and there it is!
Two words: air. fryer.