Preheat oven to 180°C/350°F (fan). Line a 900g/2lb loaf pan with greaseproof paper.
In a large mixing bowl, stir together the oil, eggs, grated courgette/zucchini, sugar and vanilla extract until well combined.
80 ml (⅓ cup) rapeseed or vegetable oil, 2 large eggs, 230 g (1 ½ cups) courgette/zucchini, 130 g (¾ cup) soft light brown sugar, 2 teaspoons vanilla extract
Gently stir in the spelt flour, cinnamon baking powder, bicarb and salt until just combined.
200 g (1 ½ cups) wholemeal spelt flour, ½ teaspoon ground cinnamon, ½ teaspoon baking powder, ½ teaspoon bicarbonate of soda, ½ teaspoon fine sea salt
Gently fold in the chocolate chips.
120 g (¾ cup) dark chocolate chips
Pour the mixture into the prepared pan. Sprinkle a few extra chocolate chips over the top.
Bake for about 50 minutes until risen and golden and an inserted skewer comes out clean. I tend to turn the pan around after about 35 minutes to ensure it bakes evenly.
Leave to cool in the pan for 10 minutes before transferring to a cooling rack to cool completely before slicing.