Jersey Black Butter and Walnut Brownies

Preheat the oven to 180°C (160°C fan/Gas Mark 4). Grease and line an 8x8 inch baking pan with baking parchment.

In a heatproof bowl set over a pan of simmering water (or in the microwave in 30-second bursts), melt the Jersey butter and dark chocolate together, stirring occasionally until smooth. Remove from the heat and stir in the Jersey Black Butter until well combined. Let it cool slightly.

Stir in the mashed Jersey Royal potato until fully incorporated and the mixture is homogenous.

In a separate bowl, whisk together the caster sugar, brown sugar, and eggs until light and fluffy.

Pour the chocolate mixture into the egg mixture and gently fold until just combined.

Sift in the flour and cocoa powder and gently fold until just combined. Be careful not to overmix.

Stir in half of the chopped walnuts and the sea salt.

Pour the batter into the prepared baking pan and spread evenly. Sprinkle the remaining walnuts on top.

Bake for 25-30 minutes, or until a skewer inserted into the center comes out with moist crumbs attached. The center should still be slightly fudgy.

Let the brownies cool completely in the pan before cutting into squares. Dust with cocoa powder (optional).