A classic American brownie with the added crunch of walnuts and the sweetness of puréed beetroot and raspberry liquor. The beetroot helps keep the chocolate base moist and adds a vibrant colour.
Preheat the oven to 190°C/375°F/gas 5. Melt the butter and chocolate in a bowl set over a pan of simmering water, making sure the base of the bowl does not touch the water. Put the eggs and sugar in a mixing bowl and beat until light and creamy. Stir in the melted butter and chocolate. Add the beetroot purée, raspberry liquor and walnuts, then fold in the flour. Pour the brownie mixture into a well-buttered baking tin, approximately 28 x 18cm (11 x 7in). Bake for 25-30 minutes, then remove from the oven and leave to cool. Turn out on to a wire rack and cut into squares. Serve with cream or vanilla ice cream.