THE CONCEPT : FILL & HEAT AT HOME
First, you toast the bun which is already stuffed with basic ingredients such as ham, cheese, grilled meats, etc., in a panini press (or heat in the oven) and then, if you like, you may add vegetables, fries & sauces. You may fill the bun with a lot of ingredients in order to maximize taste without losing sandwich integrity.
PitaPot stuffed with sliced roasted gyros and heated approx. in the oven for 8 mins @ 200 degrees (including preheat time)
If you are a retailer you may consider to enlist the following product (frozen) …
A GYROS or DONER KEBAB SANDWICH KIT
(The product below is not ours but it represents the concept / product which can be develop for you, according to your specifications, by reliable manufacturers complied with your food safety & hygiene standards).
Instead of gyros, you may also offer sliced roasted doner kebab ready to heat (e.g. pack of 300 gr.) and instead of pita (flatbread) you will offer PitaPot (e.g. pack of 3 pcs). It will be very convenient and easy for a housewife to prepare at home a gyros or doner kebab sandwich by filling the PitaPot(s) and heating them in the oven for approximately 8 minutes (or toast them in a panini press). The big advantage here is that using PitaPot, it will be very easy for someone at home to fill, heat and serve (handle) the snack, in comparison with the situation of using a classical flatbread.
You may also offer in the kit different sauces or other ingredients in order to create more added value and a premium final product (e.g. sliced roasted gyros mixed with feta cheese and green pepper). Let the user add any other ingredient he/she likes, available at home (e.g. tomato, onions, lettuce, fries).
Please note, that if you adopt the above product / concept you will get exclusivity in your country and no one can copy you for a period of 20+ years.