In a saucepot over medium heat, cook the apples in apple juice. When the apples are soft, drain the apples, but reserve the juice. Add the apples to a blender with Dijon mustard. Blend on high, adding the reserved juice, a little at a time, until smooth.

Pour the couscous into a large bowl. Add 1 1/2 cups boiling water to the couscous, cover, and let stand 10 minutes. Then, stir in the parsley, tarragon, lemon zest, and lemon juice. Season the mixture with salt, and pepper, to taste. Add the eggs and flour, and mix until thick and sticky. Form the mixture into 4 evenly portioned patties. In a large skillet over medium-high heat, heat 4 tablespoons olive oil. Cook the cakes in the hot oil until golden brown, flipping halfway through, and drain on paper towels to remove the excess oil. Keep the couscous cakes warm.

In a large, deep saucepan, combine 1 quart olive oil with a good pinch of salt, and white pepper and bring to a simmer. Season the salmon fillets with salt, and black pepper and add them to the oil in the pot, making sure they are completely submerged. Add more olive oil, if needed. Simmer over low heat and remove the salmon after 15 minutes. Cook's Note: The salmon will be cooked medium at this point. If you want it well done, keep on cooking it for 5 more minutes.

To serve, place a bit of spinach or arugula on each plate, top with a couscous cake and the salmon. Top the salmon with a spoonful of apple puree. Serve warm.