Cook the pasta in boiling salted water for 5 mins., drain, transfer to the prepared dish.
Heat the oil in a frying pan. Fry the bacon for approx. 3 mins. until crispy, add the leak, fry for approx. 3 mins., add the peas and cook for approx. 1 min. Spread the vegetables on top of the pasta. Combine the milk, sour single cream, egg and cheese, season, pour over the bake. Spread the pesto on top.
Approx. 30 mins. in the lower half of an oven preheated to 200°C.