Belgian Waterzooi with a Pie Topping

Prepare the pesto. Put the tarragon leaves, garlic, pine nuts and cheese in a blender and process everything finely. While blending drizzle in the oil in a thin stream to obtain a smooth paste and season it with lime juice, salt and freshly ground pepper. Determine the amount of oil according to your own taste.

Cook the chicken in a stock made with 2l water, the green part of the leeks, 1 stick of celery, the onion, thyme and bay leaves. Season the stock well with freshly ground pepper and salt. After 30 minutes cooking, turn of the heat and let the chicken cool down a little in the stock. Remove the chicken skin and divide the bird into 4 equal pieces. Strain the stock and reserve.

Clean the remaining vegetables, wash them and cut them into julienne (small pieces). Peel the potatoes, wash them and cut them into large dice. Cook the potatoes al dente in salted water and drain them. Melt the butter, remove from the heat and add the flour. Let it dry a little, and then add the strained stock. Let the broth boil intensively. The sauce should be a little thicker than a cream soup, so add some more stock according to taste.

Add the vegetables and cream to the sauce, return the cooked chicken and season according to taste with cayenne pepper. Roll out the pastry and cover the top of the casserole, brush with the beaten egg and place in a pre-heated oven at 220°C / 425°F / Gas Mark 7 for 10 minutes. Serve with the pesto.