Blueberry Clafoutis

I know, blueberries aren't in season, but I have a pile of them in the freezer that need using and this was a perfect Sunday lunch vehicle for them.  I use a recipe from Alice Waters' Chez Panisse 'Fruit' Book and it works every time, no matter what fruit you use (and as well as the traditional cherry, I have used many variations - raspberries, plums, figs, pears, apple and blackberry as well as this blueberry one).  It is so simple to do.  I like to bake it in a parchment-lined 20cm square tin as it seems to be moister and turns out easier.  Take 2 regular punnets of blueberries and toss in a tablespoon of caster sugar, the zest of half a lemon and a tablespoon of plain flour.  Spread the mix across the bottom of the tin, sprinkling the lemony sugar/flour over the top too.  In a bowl, mix together 3 tablespoons each of caster sugar and plain flour, 2 eggs, the zest of the remaining half of lemon and a teaspoon of vanilla essence.  Now, gradually beat in a small tub of single cream, and then fill the empty tub with milk and add that too.  Pour the batter onto the blueberries, then bake at 170 for about 35-40 minutes until puffed and set - the interior should still be a little creamy so don't overbake it.  Best served just warm.  It is rich enough as it is, but you can add a dollop of cream if you like!