Preheat oven to 350 degrees F. Oil 2 (10-inch) round cake pans.
In a nonreactive saucepan, reduce the orange juice over medium heat to 1/4 cup. Add salt, stir, and let cool.
Lightly beat eggs with paddle attachment in standing mixer on high for 1 minute until frothy. Add milk, sugar, liqueur, olive oil, reduced orange juice, lemon zest, anise and 1 teaspoon rosemary. Mix for 1 minute until well blended. Mix in the flour, baking soda and baking powder until well blended and smooth.
Pour half of the mixture into each oiled cake pan. Bake for 1 hour. Place on a rack to cool. Run a knife around the edges and place it on a plate. While the cake is still warm, smooth 3 tablespoons of marmalade onto the top of each cake. Sprinkle remaining 1 teaspoon rosemary evenly over both cakes. Garnish center with rosemary sprig. Cut each cake into wedges and serve.