Separate shared work from final assembly
Write down what the early diner can prepare once and what each person finishes for themselves. For wraps, the early diner might check the tortillas and prepare their own plate. The late diner can assemble a fresh wrap at the time they return instead of depending on a plated dinner sitting out.
Reserve a real second portion
Make the second serving deliberate. A note such as “the second tortilla pack is for Sam” prevents the early diner from using everything. If the timing is several hours apart, do not choose a dish solely because it looks good served to everyone at once.
Count the ingredients each person needs before the first serving. Two tortillas and a particular filling for the late diner are easier to protect than an informal instruction to leave “some.” Put refrigerated fillings back as directed; a label that says “for Sam” is a reservation, not a storage instruction.
Know when separate meals work better
If the later diner does not know when they will return, or the dish loses what people like about it when served twice, build two simple meals from the same shop. Tell the late diner which ingredients are theirs. Sharing a dinner plan can mean sharing the shopping and preparation without agreeing to sit down at the same hour.