If you're staying in Swellendam as a staging post on the Garden Route, I can recommend La Sosta Italian restaurant.
It's run by a former Milanese optician and his ex-banker wife (he's front-of-house, she's the chef) who decided to down-size their lives and move to South Africa.
The peasant-style food is as good as you'll taste in SA or anywhere else. Try the tagliatelle with porcini mushrooms, or the pork with apples and prunes.
We took our own wine along and they charged us a nominal sum for corkage.
They have rooms to stay, so you don't have to stagger too far to bed.
145 Voortrek Street, Swellendam
Tel: +27 28 514 14 70
Google map: tinyurl.com/yclt3lz
www.lasostaswellendam.com