- 265 ml (1 heaping cup) semi-sweet chocolate, in pieces
- 160 ml (2/3 cup) melted butter
- 95 ml (1/3 cup + 1 tbsp) sifted flour
- 1 pinch of salt
- 2 ml (1/2 tsp) baking soda
- 4 eggs
- 175 ml (2/3 cup + 1 tbs.) sugar
- 125 ml (1/2 cup) sour cream
- 100 ml (1/3 cup + 1 heaping tbsp) walnuts, crushed
- 250 ml (1 cup) mini marshmallows
- 80 ml (1/3 cup) semi-sweet chocolate chips
- Preheat the oven to 180°C (350°F).
- Place a sheet of parchment paper at the bottom of a 20 x 20 cm (8 x 8 in.) Pyrex dish, leaving the ends protrude for easy removal.
- Butter the two sides that are not covered with paper.
- Melt the chocolate in a double boiler.
- Stir in the melted butter. Set aside.
- In a bowl, combine the flour with the salt and baking soda. Stir well.
- In another bowl, beat the eggs with a whisk.
- Add the sugar while whisking to dissolve well.
- Add the melted chocolate mixture. With a rubber spatula, mix until smooth.
- Gradually add the dry ingredients, stirring gently.
- Stir in the sour cream and walnuts.
- Pour into the dish and place in the oven.
- Bake for 15 minutes then turn down the oven to 160°C (325°F).
- Bake for another 15 minutes.
- Sprinkle with mini marshmallows and chocolate chips.
- Bake for 5 more minutes.
- Turn the oven to broil and brown the marshmallows.
- Remove from the oven.
- Allow to cool for 1 hour before removing from the dish.