Step 1 Cut chicken breasts into escalopes, about 7mm-thick.
Step 2 Rub both sides of bread with cut side of the garlic clove. Spray chicken, bread and asparagus with oil.
Step 3 Preheat a barbecue or large chargrill pan over medium-high heat. Grill asparagus for 3–4 minutes, turning, until tender-crisp. Grill chicken for 2–3 minutes each side, or until cooked through. Grill bread for 1 minute each side, or until lightly charred. Set aside.
Step 4 Meanwhile, place tomatoes and watercress into a large bowl. Whisk together lemon juice, capers, olive oil and sugar. Add asparagus to the bowl with watercress and toss to combine. 5 Divide chicken and salad between four plates and drizzle caper dressing over chicken. Serve salads with a slice of grilled sourdough.