Heat oven to 200C/180C fan/gas 6. Season the chicken all over, then wrap each breast in a slice of ham. Put into a baking dish. Surround the chicken with the beans.
Dot the crème fraîche between the breast and over the exposed ends of the chicken. Dot the pesto around the chicken, too. Gently mix the beans into the crème fraîche to cover. Scatter with the cheese.
Bake the chicken for 25 mins, adding the pine nuts halfway through, until the crème fraîche has made a sauce around the chicken, and the cheese and ham are turning golden.
Serve with steamed broccoli (5-8mins in steamer depending on how crunchy you like it).
You can replace the chicken for white fish, in which case reduce cooking time to 15-20 mins depending on depth of the fish.