Measure the couscous into a bowl and add very hot chicken/vegetable stock. Swirl in your tablespoon of butter and cover the bowl until couscous is light and fluffy, about 5 mins.
Cook your rissoni in some boiling water as per packet instructions. For this small amount the microwave is ideal. Add to the couscous and fork through.
Deseed and chop your tomato. Chop your parsley. Slice the corn nibblets off the cob. Add all these ingredients to your couscous bowl. Crack in some pepper.
Pour french dressing into your salad a tablespoon at a time, you only want enough to just give flavour and this is a very easy salad to drown. Spoon into your serving bowl and crack more pepper over the top. Chill and serve.
You don't have to have the rissoni but I like it for a little contrast in size to the couscous.
Of course add more of any ingredients if you wish to your own taste but watch the dressing, you can't undo it.