An egg dish. Frittata?

I wouldnt consider tea sandwhiches a make-ahead food, and they'll take some time to assemble the morning of. COnsider replacing them with mini quiches? That you can def. do ahead of time, and still meets the "filling" 'real food' requirement

I’m the PP who recommended the tea sandwiches (it’s just a fancy way to say mini or finger sandwiches) you can make the tuna salad the night before and cut the croissants in half, put them in a gallon sized ziplock and then in the fridge to keep them fresh, you won’t want to assemble them until the day of or the tuna will turn the croissants soggy. I would do the roast beef and swiss on sourdough or rye since you’re already making crescent bacon bites & tuna salad on croissants. If you’re not doing super rare roast beef you could put them together the night before but hold off on the mayo and serve it on the side, you will want to plate them on a platter and wrap really well with plastic wrap. I tend to opt for turkey & ham if I’m making them the night before because I think they hold up a little better.