1.Place the water in large saucepan; bring to a boil. Add polenta in a slow, steady stream, stirring constantly. Reduce heat; simmer, stirring constantly, about 20 minutes or until polenta thickens. Stir in cheese, basil and butter. Spread polenta evenly in lightly oiled 19cm x 29cm slice pan. When cool, cover; refrigerate about hours or overnight.
2.Meanwhile, heat oil in medium saucepan; cook onion and capsicum, stirring, until onion softens. Add zucchini and eggplant; cook, stirring, 3 minutes. Stir in tomato, sambal, paste and stock; bring to a boil. Reduce heat; simmer, uncovered, about 8 minutes or until mixture thickens. Stir in chives.
3.Turn polenta onto board; trim edges. Cut polenta into quarters; cut each quarter in half diagonally to form two triangles. Cook polenta triangles on heated oiled grill plate (or grill or barbecue) until browned both sides and heated through; cover to keep warm. Cook sausages on same heated oiled grill plate (or grill or barbecue) until cooked through.
4.Serve sausages on ratatouille with polenta triangles.