Preheat the oven to 200C/gas
6/fan 180C. Put the butter, flour and
milk in a pan and whisk over a
medium heat until the mixture boils
and thickens. Reduce the heat and
simmer for 5 minutes. Remove
from the heat, stir in the Parmesan
and half the gruyère and season
with salt and ground black pepper.
Pour one third of the sauce into a
bowl and stir in the pesto. Lay out
the pancakes and spoon a dollop of
sauce in the centre of each one.
Top with the chicken and artichokes
then fold in the sides of the
pancakes and roll them up.
Arrange the pancakes in a single
layer in a buttered large shallow
baking dish (about 25 x 30cm) and
pour over the remaining sauce.
Scatter with the rest of the gruyère.
(If making ahead, cool, cover and
chill for up to a day, or freeze for up
to a month.)
Bake, uncovered, for 30 minutes
until the sauce is bubbling and
golden. Serve with a green salad.