This tart is one of my favorite combinations – Lemon and lime to me is so much more refreshing than just plain old lemon. If you want to bring out the fragrance of the lime even more, simply grate the zest of 4 limes and add to the filling mix at the beginning. This filling isn’t made from a curd recipe, it’s gently baked in the oven after you have baked the pastry shell blind, so you are left with a really soft and silky filling and a short crisp pastry shell.
With this particular tart, as it has a moist filling, it's important to egg-wash the uncooked tart shell before adding the filling. This adds a sort of waterproof layer and keeps the pastry crisp and short for longer.
Whisk together the sugar and eggs in a bowl. When they are well mixed, slowly stir in the cream and the juices. Put the cooked tart shell back into the oven and then pour the filling into it -- I find this reduces spillage. Bake for around 40 to 45 minutes at 180C/350F/Gas 4 or until the filling is set, but still semi-wobbly in the middle (obviously different ovens will cook at different rate so it is good for you to try this tart a couple of times to gauge exactly when you should take it out of the oven). After cooling for an hour, the semi-wobbly filling will have firmed up to the perfect consistency; soft and smooth. If you cut it before it has had time to rest it will pour out or be extremely gooey.
You can dust it with a little icing sugar, if you wish. Serve with a huge pile of fresh raspberries or strawberries. Whatever you decide to serve it with should be quite simple so that you let the tart do the talking.