One of my favorite spring and summer desserts is a lemon tart with berries and whipped cream. This is one of those pastries where everything melds into the perfect balance of flavors and textures -- the lemon's tartness nicely contrasts the sweetness of the berries and the luscious cream ties it all together. If you have Meyer lemons, so much the better as they are sweeter and have a more complex citrus flavor then the standard variety.
Lemon tart with berries is also the ideal dessert for anyone wishing to make a dish from local and seasonal ingredients. Strawberries, raspberries and blackberries are popping up in markets and backyards throughout the area. Meyer lemons are also in abundance right now. You can find them at most farmers' markets, and maybe even closer by in a neighbor's yard (or your own) as they grow beautifully in the Bay Area. If you don't have your own tree, but have seen one at someone else's house, I bet they'd share if you asked nicely and promised to bring over a nice slice of tart.
I've tried numerous lemon custard recipes, but my favorite is the Tarte au Citron recipe in the Bouchon cookbook by Thomas Keller. And, as luck would have it, this recipe is freely available at Epicurious.com, so you don’t have to buy the book to get it (although if you're in the market for a gorgeous book full of amazing recipes, I recommend it). I love Mr. Keller's lemon sabayon because the consistency lies beautifully in the tart crust, it isn't too eggy and the lemon flavor really shines through. Also, don't let the fact that you need to cook the custard in a bowl over a pot of simmering water dissuade you. This is not hard to make.
The Bouchon recipe calls for a pine nut crust, which I have made in the past and liked. That said, I prefer to make a regular butter crust for my tart as I think the lemon and berry flavors are interesting enough on their own and don't necessarily need a nutty component.