Agree with the hot milk.
We actually use almond milk. Mix a small amount of chocolate powder with milk to make a paste then mix that in the hot milk.
You can use any chocolate that’s decent. I wouldn’t use Hershey personally

I scored some free packets of Hotel Chocolat’s chocolate mixes when they were closing their Union Station store and giving away during the Covid shutdown when I had to work in person. It’s made of fine chocolate flakes and makes a nice thick cup. They sell online now.

Abuelita squares (well, triangles really) if you like Mexican style, with a hint of cinnamon.

Overall, the trick is to use hot milk, not hot water. Even Hershey’s cocoa powder from the tin is OK with milk.

French person here. I had no idea there was supposed to be a difference between European and American hot choc.

I buy good quality dark chocolate, melt it slowly, and add warm milk. You can make it as thick as you like, and the sweetness will depend on the cacao percent of the chocolate. I buy chocolate that's at least 70%. The ready-made is always too sweet.

Has anyone bought the bottled Angelina hot chocolate or similar style French/Italian/Spanish thick hot chocolate? Any recs for brands available here? Not too sweet and not too thin. Thanks!