Winter is citrus season, and that means that oranges, mandarins, lemons, limes, kumquats and grapefruit are at their peak of flavor and juiciness, and the essential oils in their zest are intense. Just scratch the skin of a piece of citrus – any kind – and take a whiff. That’s how my friend, Bill Fujimoto, the former owner of Monterey Market in Berkeley, California, used to evaluative the quality of the citrus that arrived at his loading dock. An intense aroma is an indicator of a fruit at its prime.

The Mediterranean’s region, like much of California, the southwest and Florida, is citrus country. Groves of oranges stretch out of Seville, Spain to the sea. Blood oranges thrive on the coast of North Africa and Italy, and Menton, on France’s Riviera is famous for its oranges and lemons.

BLOOD ORANGES
My first experience of blood oranges was many years ago when I was working in the vineyards in Southern France alongside a man from Algeria who shared his oranges with me and my daughter. The rind, like the flesh inside, was the color of rubies, and tasted like a combination of raspberries and oranges. After that, I sought them out in the markets of Provence, and eventually, here at home in California, I planted my own trees, now more than 20 years old.

Blood Orange, Anchovy, and Olive Salad
A French friend who was visiting me one January showed me how to make this classic North African salad. She grew up in France during World War II, in the Alps, and an orange, any kind, was a once in a year treat. She was thrilled to pick oranges from my trees, and equally excited to compose this salad which she had had on a recent trip to Morocco with her son. For maximum flavor, be sure to use good quality anchovies, packed in olive oil. You can use either black or green olives, but I prefer the salt-cured, wrinkly black ones. They look beautiful dotting the  dark-red fruit.

4 blood oranges
4 to 6 olive-oil packed anchovies
10 to 12 salt-cured black olives
2 tablespoons extra-virgin olive oil

Slice the oranges crosswise into thin rounds, then cut away the rind and remove the seeds. Arrange them in concentric circles on a serving platter. Arrange the anchovy fillets and olives on top and drizzle with the olive oil.

Cover with plastic wrap and refrigerate 5 or 6 hours or overnight.

Remove from the refrigerator about 30 minutes before serving.
Serves 4

Blood Orange Upside Down Polenta Cake
This is a good ending for a rich meal, because, surprisingly, the cake, while intensely flavorful, is not overly sweet. The recipe is adapted from the March 2010 issue of Bon Appétit. I have a Le Creuset Tarte Tatin baking dish with handles which makes it so easy to flip the cake onto a serving plate. I highly recommend it. And, if an orange slice should stick, don’t worry. Just gently unstick it and place it where it belongs on the cake.

Cake
7 tablespoon sugar, plus ¾ cup
3 tablespoons water
8 tablespoons butter at room temperature, cut into 1 tablespoon slices
3 to 4 unpeeled small to medium blood oranges (the cooked skin and pith are delicious)
¾ cup plus 3 tablespoons all purpose flour
3 tablespoons polenta
1 ½ teaspoons baking powder
¼ teaspoon fine sea salt or kosher salt
6 tablespoons milk
1 inch piece of vanilla or ¾ teaspoon vanilla extract
2 large eggs, separated
For the Crème Fraiche Sauce
1 cup chilled crème fraiche
1 tablespoon sugar

Preheat an oven to 350 degrees F. Combine 6 tablespoons of the sugar and the water in a 10-inch diameter ovenproof skillet with 2 ½ inch high sides. Place over medium high heat, and heat until the sugar dissolves, about 1 minute. Increase the heat and boil without stirring until the syrup is golden amber, but not dark amber, occasionally brushing the sides with a wet pastry brush and swirling the skillet, about 4 minutes. Remove from the heat and whisk in 2 tablespoon of the butter into the caramel. Set aside.

Cut off both ends of the oranges and slice them into 1/8-inch thick rounds. Remove and discard any seeds. Arrange orange slices over the caramel mixture, in concentric circles, overlapping them.
In a medium bowl, whisk together the flour, polenta, baking powder, and salt to blend. In another, large bowl, using an electric mixer, beat together the ¾ cup of sugar and the remaining 6 tablespoons of butter. Split the vanilla bean and scrape out the inside, adding it to the sugar and butter. Beat until light and fluffy.

Add the egg yolks one at a time, beating well after each addition. Add the flour mixture in 3 additions, alternately with milk in two additions, beating batter until just incorporated.
Using clean, dry beater beat the egg whites in a large bowl until soft peaks form. Add remaining 1 tablespoon sugar and beat until stiff but not dry. Fold ½ of the egg whites into the batter to lighten, then fold in remaining egg whites in 2 additions. Drop batter by large spoonful atop orange slices in skillet, then spread evenly.

Place in the center of the oven and bake until tester inserted in center comes out clean, 35 to 45 minutes. Cool cake in the skillet 10 minutes, then loosen the edges. Place a platter atop the skillet. Using oven mitts hold platter and skillet firmly together and invert, allowing cake to settle on the platter. Rearrange any orange slices that may have become dislodged. Let cool slightly before serving.

Sauce

Using an electric beater, beat the crème fraiche and the 2 tablespoons of sugar in a medium bowl until thickened, about 2 minutes.

Serve cake warm or at room temperature, cut into wedges and topped with a dollop of the sauce.

Serves 8 to 10.

MEYER LEMONS
I am a big fan of Meyer lemons. They have a thin, tender skin and are sweeter than the Lisbon or Eureka lemons, and are thought to be a wild cross between a lemon and a mandarin. I have to admit I was as fascinated by the history of the Meyer lemon as I was enamored of its delicate skin and sweet tart juice. The Meyer lemon, like many citrus, originated in China, and it is thought to be the result of a naturally occurring cross between a lemon and an orange or mandarin. Frank N. Meyer, a plant explorer for the USDA, introduced it into the United States in 1908, and it became a popular backyard fruit in California and elsewhere in the southwest, partly because it is more cold tolerant than other lemons.

Then, in the 1940s, it was discovered that the Meyer lemon was a carrier of a deadly citrus disease and the trees were pulled from nursery propagations and destroyed, except for one strain that was found free of the disease. Happily, by the 1970s, it was deemed virus free and received certification to that effect from the University of California. This particular clone was propagated and became known as the Improved Meyer Lemon which is the tree that is sold today – and the variety that we planted now almost 25 years ago when my husband and I moved into the old wooden farmhouse where we live now. We spaced them to frame the south side of the house from sun porch to kitchen. We keep them trimmed, like a hedge, to just about 7 feet, and it is very convenient to have them in easy reach of the kitchen windows.

I use my Meyer lemons for salad dressings, marinades, for fish, and for this incredible lemon tart, and soon will  use them in making Sel d’Agrume for La Vie Rustic.

Tarte au Citron

This has a crumbly sweet crust and a dense, intensely flavored layer of pure lemon custard that forms a lovely golden skin on top as the tart cooks. Don’t be scared that the filling seems a bit shaky – it will set as it cools. And, if you are not using Meyer lemons, add another 2 to 4 tablespoons of sugar.

For the pastry
1 1/2 cups all-purpose flour
1/4 cup sugar
1/2 cup cold butter, salted or unsalted, cut into small pieces
1 large egg
For the filling
4–5 Meyer lemons, to make ¾ cup juice
1 1/4 cups sugar
2 large eggs
10 tablespoons butter salted or unsalted, melted

Preheat the oven to 350ºF. Have ready a 9-inch tart pan with a removable bottom.

To make the pastry, in a bowl, combine the flour and 1/4 cup of the sugar and stir until well blended. Add the butter and, using and using a pastry cutter, cut until the mixture is crumbly. Add the egg and, using a fork, mix it into the dough. Using your fingers, press the dough evenly into the tart pan; the crust should be about 1/4 inch thick.

Line the crust with aluminum foil or parchment paper and fill with pie weights or dried beans. Bake until slightly firm, about 10 minutes. Remove from the oven and lift out the weights and liner. Prick any bubbles with the tines of a fork and return to the oven until firm and barely colored, about 5 minutes longer.

Finely grate the zest of 2 of the lemons. Halve, juice and seed as many lemons as needed to measure 3/4 cup lemon juice.

In a bowl, using an electric mixer, beat the sugar and the eggs until pale yellow. Gradually pour in the melted butter, beating constantly. Stir in the lemon zest and juice. Gently spoon the filling into the pastry shell. Bake until the crust is golden and the filling is lightly golden and firm to the touch, about 25 minutes. Transfer to a wire rack to let cool completely before serving.

Serves 10

SEL D’ AGRUME
By mid-January, Sel d’ Agrume, made with my blood oranges and Meyer lemons will available and ready to ship. Think of using it to rub a turkey or a flank steak for the grill, for adding to Sangria, or sprinkling a bit on chocolate mousse or brownies. Like La Vie Rustic’s other Sel de Fruits, the base is coarse sea salt from Guerande in France.

JAMBON CRU
January and February are, for most of us, cold months, and are ideal for preparing Jambon Cru, or French-style prosciutto. In France, this is the traditional time of year, the cold months, when fresh hams are salted and cured. Start now, and you’ll be using your homemade jambon cru to wrap your melon slices to stuff your figs in summer. La Vie Rustic’s DIY set, with its redwood salting box securely constructed with brass screws, ready-made curing rub, fine-mesh cheesecloth, butchers’ string and straightforward instructions makes it easy.