Cary Grant said that cliches become cliches because they're true. Rudbeckia 'Goldsturm' and aster 'Mönch' or else 'Little Carlow' have become gardening cliches, or if you prefer a classic plant combination, because they work so well together.
Rudbeckia fulgia var. sulliviani 'Goldsturm', photo by Lukas Riebling
Aster x frikartii ‘Mönch’'
The two work so well together because the aster not only looks good with the rudbeckia, its blue cooling the other's brassy yellow, but because it can stand up to the somewhat bullying demeanour of black-eyed susans, who tend to run at the roots. Although, having said that, 'Goldsturm' is pretty well behaved. It runs a bit, but not uncontrollably.