For the tomato couscous, place the vegetable stock, tomato purée and tomato ketchup into a small saucepan and bring to the boil.
Place the couscous into a large bowl and pour over the stock mixture to cover the couscous. Cover with cling film and leave to stand for five minutes.
Remove the cling film and separate the couscous grains with a fork. Add the cherry tomatoes and herbs, season, to taste, with salt and freshly ground black pepper and stir well.
Preheat the oven to 200C/400F/Gas 6.
For the goats' cheese roll, place the puff pastry onto a board. Place the basil leaves along the middle of the pastry and top with the goats' cheese log.
Brush the edges of the pastry with beaten egg, then roll up to seal the goats' cheese inside the pastry. Brush the top of the pastry with more beaten egg and sprinkle with sea salt.
Place the pastry roll onto a non-stick baking sheet, transfer to the oven and bake for 12-14 minutes, or until the pastry is puffed up and golden-brown on top. Slice in half.
To serve, place equal amounts of the couscous onto two serving plates and place half of the goats' cheese roll on top of each.