Servings: 1 9x13-inch (3.5 l) pan, which cuts into 24 squares
4 oz (120 g) unsweetened chocolate, chopped
⅔ cup (150 ml) boiling water
2 cups (420 g) sugar
⅔ cup (150 g) mayonnaise
3 large eggs, room temperature
1 tsp (5 ml) vanilla extract
1 cup (130 g) all purpose flour
½ cup(105 g) cocoa powder, sifted
½ tsp (2 ml) salt
1 cup (180 g) chocolate chips
1. Preheat oven to 350°F (180°C). Grease and line a 9 x 13-inch (3.5L) baking pan with parchment paper so that the paper comes up the sides.
2. Place the chopped chocolate in a large bowl and pour boiling water overtop. Let the chocolate mixture sit one minute, then whisk to melt.
3. Whisk in the sugar, then add the mayonnaise and then the eggs, one at a time, stirring well after each addition. Stir in the vanilla.
4. With a wooden spoon or spatula, stir in the flour, cocoa powder and salt until evenly blended. Stir in the chocolate chips
5. Scrape the batter into the prepared pan and spread evenly. Bake for about 30 minutes, until a tester inserted in the centre of the brownies comes out clean. Cool to room temperature.
6. Brownies slice best when chilled, but taste best at room temperature.
Once sliced, you can store the brownies in an airtight container for up to 5 days.