Open-Faced Pickled Asparagus Sandwich

Ingredients

• 1 bunch asparagus spears, washed and trimmed
• 1 cup water
• 1 cup white vinegar
• 1 tablespoon salt
• 1 tablespoon sugar
• 2 garlic cloves, peeled and smashed
• 1 teaspoon mustard seeds
• 1 mini baguette
• 1 tablespoon mayonnaise or aioli
• 1 hard boiled egg
• 1 tablespoon chopped red onion
• Fresh dill sprigs