Marrow Bone With Chimichurri and Onion Recipe

Ingredients

• 6 12cm pieces marrow bone, halved lengthways (see note)
• 2½ tbsp sea salt flakes
• 6 5cm-thick slices white bread
• For buttering: softened butter
• Caramelised onion
• 2 tbsp grapeseed oil or olive oil
• 2 white onions, finely diced
• Chimichurri
• 3 garlic cloves
• ½ jalapeño chilli, coarsely chopped, half the seeds reserved
• ½ cup (firmly packed) flat-leaf parsley, finely chopped
• 80 ml extra-virgin olive oil (1/3 cup)
• 70 ml white vinegar
• 2 tbsp (firmly packed) oregano, finely chopped
• 2 tsp dried red chilli flakes