Prepare the oven and tin

• Preheat the oven to 175 °C.
• Line an 8x8 inch tin with baking paper.

Melt the chocolate

• Place the chocolate chips in a bowl over a saucepan holding two inches of water.
• Melt over low heat, stirring until smooth.

Cook and purée the squash

• Boil the peeled, chopped butternut squash in a saucepan for 10 minutes.
• Drain well, then blend into a smooth purée.

Make the batter

• Add part of the squash purée to the melted chocolate.
• Mix well until fully combined.
• Pour the batter into the prepared tin and spread it evenly.

Bake the brownies

• Bake for 25-30 minutes, until a skewer inserted in the middle comes out clean.
• Let the brownies cool completely.

Frost and cut

• Melt the remaining chocolate the same way as before.
• Stir in the rest of the squash purée.
• Spread the frosting over the cooled brownies and cut into squares.