You can use the 1 syn for every 20 calories rule for things like the chilli mix that have no free food allowance.
Check the calories on the back but make sure you work it out for calories for just the dry mix as some packets give you calorie info of whole meal made up as suggested
Have you tried the Asda Vegetable Chilli, its in a 400g Can but its syn free on EE and Green and tastes lovely! Tescos do something similar with 1 syn for the tin if you dont live near an asda