Argentinian Chorizo Hot Dogs (Choripan)

Ingredients

• Chimichurri Sauce

  • ⅓ cup (75 ml ) olive oil, plus more for brushing
  • 3 tbsp (45 ml) red wine vinegar
  • ¼ cup (10 g) parsley, finely chopped
  • ¼ cup (10 g) cilantro, finely chopped
  • 1 garlic clove, finely grated
  • ½ red onion, finely chopped
  • ½ jalapeño chili pepper, seeded or not, finely chopped

• Sandwiches

  • 4 submarine buns, each about 6 inches (15 cm) long
  • 4 chorizo sausages (see note), halved lengthwise
  • Mayonnaise, to taste
  • 1 tomato, seeded and cut into small dice