The Best Hot Chocolate uses high quality chocolate and will be low FODMAP if made with lactose-free milk - and if you heed the servings sizes.
Bring the milk to a simmer in a saucepan, then remove from heat. Whisk in the chocolate then cover and let sit for a minute or two. Whisk again to help chocolate melt and incorporate with the milk. Whisk very well until blended and smooth.
Cover and let sit for a few minutes; this rest allows it to thicken slightly. Divide into cups and serve immediately.