You need Welsh butter. Anything else tastes plain and dull now.
Perfect toast, for me, is Hovis best of both* with loads of welsh butter so it stays liquid on top, then spread about half as much nutella on thoroughly so thewarm butter gets mixed with the warm nutella. If you get the ratios right and mixed well the result is incredible, very different and vastly better than nutella on toast any old way.
* not the best bread of course but you need something dense so the butter doesn’t sink in too much. White sliced or best of both is needed for this critical procedure