Butter and sugar amounts are guesstimates as I tend to eyeball it until the consistency I prefer.

Peel and cut up all sweet potatoes into chunks or coins. Place in a casserole dish.

Stir in brown sugar and keep stirring until fully mixed and bubbling.

Bake on 180°C for at least 1 hour or until tender.

Remove foil and let bake for 20 more minutes until browned.

Add marshmallows on top and bake until melted and toasted.