Place a small saute pan over medium-low heat and add the Marsala and raisins. Allow to simmer for a few minutes for the raisins to absorb the Marsala and plump.
Place a high-sided saute pan over medium-high heat and add about 2 to 3 tablespoons blended oil. Once heated, add the cauliflower and season with salt. Add the shallot, garlic, and season with salt, to taste. Stir to combine and add the drained capers, toasted pine nuts, 1/2 to 3/4 cup unsalted butter and saute. After about 2 minutes, add the raisins, Marsala, orange zest, and splash Champagne vinegar. Taste the cauliflower mixture and season with salt and freshly ground black pepper, to taste, if needed. Stir to combine and turn the heat down. Keep warm until fish is done.
To another saute pan over medium-high heat, add 2 tablespoons blended oil. Season the fish medallions with salt on both sides and add to the heated pan. Sear the first side for about 2 to 3 minutes, until golden brown. Flip and add about 1/2 cup unsalted butter, the orange juice and baste the fish with the orange-brown butter until cooked through, about 2 more minutes. Turn off the heat and stir in the parsley.
Place some of the cauliflower onto a plate. Top with a piece of fish and spoon some of the sauce around the plate.