How to design an "add n rows" button?

In a web app I have a table with some editable data (e.g. inputs, checkboxes), e.g. theKnot

I'd like to have an add row functionality with option to add multiple rows at once. What would be the best design for this? An input and a button reading "add guests"? How would you add one guest, then? Or is there a pattern for this?

I was also thinking by adding new row via hotkey (e.g. Ctrl + Shift + Enter), but it's not that discoverable though.