Don’t start with cold cheese. The amount of time it takes to brûlée the surface won’t be long enough to heat the entire paste through.
Consider one wrapped in bark. “They are self-contained by their cambium belts, which makes them easy to serve and eliminates the need for a baking dish.”
The broiler method works just fine, but everybody’s oven is a little different, so if you’re doing this for the first time, you’ll definitely need to pay close attention to your cheese under the flame.