• Preheat the oven to 350 F. Line an 8” square baking pan with parchment paper.

To make the graham blondies

• Brown the butter (place it in a frying pan and cook as it melts then sputters and spits until you can see brown bits at the bottom stir with a rubber spatula or wooden spoon until the butter has gone almost silent and there’s lots of brown bits, immediately remove from heat less it burn). Let cool slightly.
• Grind the graham crackers into a powder using a food processor.
• Add the sugar, salt and vanilla to the butter and whisk to combine. Add the egg and yolk and whisk well, for a full minute. Use a rubber spatula to mix in the graham crumbs and flour.
  
• Spread the batter into the pan, using the back of the spatula or your hands to flatten it into an even layer. Bake for 20-25 minutes, until browned on the edges. Let cool fully while you make the ganache.
  

To make the ganache:

• Chop the chocolate up very, very finely and set in a heatproof bowl. Heat the heavy cream in a pot over low heat, until it’s steaming and bubbles at the sides. Pour it over the chocolate and stir briefly, then leave it to melt the chocolate for a full minute. Stir until completely smooth and shiny. Pour over the cool blondies and set in the fridge to firm up.
• Once you have your chosen topping on (marshmallow or meringue) use a kitchen torch to toast the top. If you don’t have a kitchen torch you can use your oven’s high broil feature, although you might want to let it cool before slicing.