Grilled Asparagus with Ginger Sesame Dipping Sauce

Ingredients

• 1/4 cup Japanese mayonnaise
• 3 tablespoons red miso
• 1 tablespoon freshly squeezed lemon juice (about 1/2 medium lemon)
• 1 tablespoon minced white or yellow onion
• 1 teaspoon toasted sesame oil
• 1 tablespoon finely grated fresh ginger
• 1 green onion, green tops only, cut into 1/16-inch thick slices, for garnish (optional)
• 1 fresh asparagus spears, tough ends removed
• 2 tablespoons neutral-flavored (oil grapeseed or canola), plus extra for oiling grill
• salt and freshly ground black pepper,
• toasted sesame seeds, for garnish
• 12 6-inch bamboo skewers, soaked in water for 30 minutes to 1 hour