Chicken thighs simmered in coconut milk with green curry paste, tamarind and Thai basil.
This one's already gluten free as written. Just check the label on your green curry paste and fish sauce, some brands add wheat-based thickeners.
Cut the chicken pieces roughly the same size so they all finish at the same time. Check one of the bigger pieces at 15 minutes before assuming the whole batch is done.
I like to cube up an aubergine and throw it in with the chicken. It soaks up the sauce well and gets plenty of time to soften over the full cook. Sugar snap peas or mangetout work too if you want something with more crunch, just add those in the last 3–4 minutes so they keep their bite.