Photograph: Dan Jones
Preheat the oven to 220°C, fan 200°C, gas 7. Toss the potatoes in 1 tablespoon olive oil in a large roasting tin, bash the 3 garlic cloves and add to the tin. Season; roast for 20 minutes.
In a food processor, whiz the bread into crumbs, add half of the herbs, half the remaining garlic clove, ½ tablespoon olive oil and ½ tablespoon water; pulse to combine. Tip into a bowl and stir in the parmesan and lemon zest; season. Press on to the chicken.
Remove the roasting tin from the oven and add the chicken. Squeeze over the juice from half the lemon and roast for 10 minutes. Add the asparagus, then roast for 10 minutes.
Whiz the remaining herbs with the remaining garlic, lemon juice and olive oil, a little water and the capers; season. Serve with the chicken.