Carrot cake Weet-bix slice

Ingredients

• 5 Weet-Bix, crushed
• 1 1/2 cups white self-raising flour (195g)
• 1 tsp cinnamon
• 1/4 tsp salt
• 1 cup grated carrot (100 g)
• 1/3 cup walnuts, roughly chopped (50 g)
• 180 g margarine
• 1 cup granulated sugar (200 g)
• 1/4 cup orange juice, no added sugar
• Icing
• 125 g light cream cheese, room temp
• 1 tbs margarine, room temp (20 g)
• 1/4 cup icing sugar (30 g)
• Zest of 1 orange
• 1 – 3 tsp milk of choice, if needed