Use a dish with room for the marshmallows
Check the small ovenproof dish before chopping the chocolate. The cream and chocolate are warmed and stirred together first; the marshmallows are arranged afterward. Put them upright with enough room to see the tops, instead of burying them in the chocolate at the beginning. Keep dry mitts and a heatproof landing place ready for both trips from the oven.
Watch the second baking stage closely. Lightly golden edges and soft marshmallows are the goal, rather than dark tops. Keep the short standing period before adding faces, then warn guests that the dish remains hot even when the surface looks ready to dip. Set the crackers beside it with room to rest a plate instead of asking people to reach across hot cookware.
