The key to the best Pea and Ham soup is the timing: Make sure you have Green/yellow split peas in the cupboard whenever you buy a ham!
Boil the ham,(with onions, veg, herbs, spices or whatever you have that needs boiled up), remove it to do the honey roast bit, and bung in the peas (And NO salt).
Simmer until the ham's ready. Eat the ham.
Leave the soup overnight, and eat the next day, after boiling/simmering until just your fave texture.
If you really manage to get ahead of yourself, you can pre-soak your peas the night before, and then cook the ham in that water; this way, the soup might be ready to eat before the main course is cooked.
I managed it once, but I think the soup tastes better, if left to stew overnight.
Rob