01 -
Put the sweet potato cubes in a large pot filled with salted water. Boil them for about 15-20 minutes or until they're soft.
02 -
Drain the sweet potatoes, then put them back in the pot. Mash them up with a masher or a hand blender until you get a smooth texture.
03 -
If needed, roughly chop the pre-cooked chestnuts. Stir them into the mashed sweet potatoes.
04 -
Blend in the vegetable broth and butter. Add salt and pepper, and stir until it's as creamy as you want.
05 -
Taste to check the seasoning and adjust if needed. Serve it warm.