Heat oven to 220C/fan 200C/ gas 7. Season the inside of the poussins generously with salt and pepper, then stuff each with a garlic clove, half a bunch of thyme and a lemon half. Sit the birds in a shallow roasting dish. Smother generously with butter, then season the skin with sea salt and black pepper. Roast in the oven for about 40 mins. While the birds are roasting, prepare the accompaniments. For the braised peas and lettuce, heat a frying pan and add a drizzle of oil. Sizzle the bacon for 2 mins until starting to crisp. Turn down the heat a little, toss in the onions, then continue to cook for 6-7 mins until they are golden. Pour the chicken stock into the pan, simmer for 2 mins, then scatter in the peas and cook for 2 mins more. Lastly, stir in the lettuce and cook for 1 min until just wilted, then set aside. For the spring vegetables, bring a large pan of salted water to the boil and have a bowl of iced water at the ready. In batches, boil all the veg (except the radishes), then transfer to the iced water. The courgettes will take 3 mins, the carrots and leeks 2 mins. Drain the vegetables, then lay them on kitchen paper to dry. Heat a drizzle of olive oil in another frying pan, then stir-fry the vegetables until just starting to colour. Add the vinegar, lemon zest and a little seasoning. Turn off the heat, toss through the radishes, then drizzle with a little more oil. Check if the poussins are cooked by inserting a skewer or small knife between the leg and the breast; if the juices are pink, give the bird an extra 5-10 minutes in the oven. Once ready, remove the poussins from the dish and leave to rest, upside down, for 10 mins (this keeps the breasts from drying out). To make a simple gravy, remove the lemon halves from the poussins, squeeze into the juices in the roasting dish, then whisk together. Strain the lemony juices into a jug. You are now ready to carve the birds and plate up. Using a sharp knife, cut through the thigh joint and remove the leg. Cut each leg through the joint to separate the drumstick from the thigh. Carefully carve the breasts away from the bone, cutting through the joint to leave the wing attached. Carve each breast into 2 pieces so each portion has 2 pieces of leg and 2 pieces of breast. Spoon a mound of the braised peas and lettuce into the centre of 4 large, shallow, bowls. Neatly assemble a ‘nest’ of vegetables around the lettuce. Pile the carved poussin on top of the lettuce, giving each serving the same amount of meat. Pour over the lemony sauce and serve straight away.
