Mackerel Asparagus Salad with Sesame Vinaigrette

Ingredients

• 7 ounces (200g) green asparagus, ends trimmed
• One 4.4-ounce (125g) tin of mackerel in sunflower oil, drained
• Extra-virgin olive oil, as needed
• Kosher salt and freshly ground black pepper, to taste
• 1 scallion, thinly sliced
• Handful of purple shiso leaves (optional)
• Sesame Vinaigrette
• 2 tablespoons sunflower oil or neutral vegetable oil
• 1 tablespoon white sesame seeds
• 1 tablespoon black sesame seeds
• 3 tablespoons rice vinegar
• 3 tablespoons mirin
• 1½ tablespoons soy sauce