To make the pangrattato, preheat the oven to 180°C (160°C fan-forced) and line two trays with baking paper.
Toss the breadcrumbs with the lemon zest, grated garlic, 2 tbsp of olive oil, salt and paper. Spread evenly on one tray.
Spread the almonds on the second tray. Cook both the almonds and the breadcrumbs for about 10 minutes, shaking half way through.
Allow the almonds to cool, then chop coarsely with a knife and toss into the breadcrumbs. Sprinkle over the grilled asparagus. If making the pangrattato in advance, allow to cool completely before storing in an airtight container.
To cook the asparagus, preheat the grill to 200°C and line a shallow tray with foil. Lay out the asparagus spears flat, drizzle with the remaining olive oil, season with a little salt and pepper and grill for about 5 minutes.
Serve the asparagus straight from the grill or at room temperature. Drizzle with the lemon juice, sprinkle with the pangrattato and serve immediately.