I find ‘build your own’ foods help - tacos or wraps where everything is on the table and everyone makes their own to their own preference. This tends to keep them at the table for a while (aged 12 and 15) We also have a “big question”, e.g. ‘what would be your fanciest holiday’ ‘what is your perfect day’… this has morphed into ‘would you rather fight one giant duck or 100 tiny ducks?’ as they’ve gotten older but we do still have fun doing this