Ingredients:

· ½ cup unsalted butter, melted

· 1 large egg

· 1 cup light brown sugar, packed

· 1tbsp vanilla extract

· ¼ cup unsweetened natural cocoa powder

· 2 vials red food colouring, or as needed

· ¾ cup all-purpose flour

· Salt, optional and to taste

· ½ cup semi-sweet chocolate chips, melted

Method:

Preheat oven to 175°C. Line an 8-inch square baking pan with aluminum foil, spray with cooking spray and set aside. In a large, microwave-safe bowl, melt the butter. Wait momentarily before adding the egg so you don't scramble it. Add the egg, brown sugar, vanilla, cocoa, and whisk until smooth. Add the red food colouring and whisk to incorporate. You will need a lot of it because it takes a lot to turn a chocolatey batter red. Keep adding until desired shade is obtained. Add the flour, salt, and stir until just combined; do not over-mix. Turn batter out into prepared pan, smoothing the top lightly with a spatula and set aside. In a small, microwave-safe bowl, melt the chocolate chips in 10-second bursts until chocolate can be stirred smooth.

To create the pattern, drizzle chocolate over batter in five wide, evenly spaced, parallel lines, each spanning the length of the pan. Rotate pan 90-degrees and with a toothpick, starting at the top of the pan, create the swirls. Bake for about 28 to 30 minutes, or until a toothpick inserted in the centre comes out clean. Allow bars to cool preferably over night or for at least 30 minutes before slicing.