To begin the creamed leeks, heat the olive oil and butter in a medium saute pan over medium heat and saute the onions until translucent. Deglaze
the pan with wine and add the leeks, cooking gently until the liquid is almost all gone. Make a slurry
by gradually adding the cornstarch
to the cream, and then whisk
in the Parmesan
. When the wine
has mostly evaporated, stir the slurry mixture into the leeks, season with salt and pepper, and reduce heat to a simmer
to allow reducing and thickening. Set aside in a warm place.
Slice each fish fillet
in half lengthwise. In a plastic bag, shake together cornmeal, flour, garlic
pepper seasoning, and salt. Moisten fish by dipping in milk and shake in bag to coat with cornmeal
mixture. Heat olive oil
and butter over medium heat in a large skillet, and cook each side of coated fish until golden brown. Do not overcook the fish - it is done when it springs back upon gentle prodding.
Spoon some leek ragout in the middle of serving plate, top with tilapia, and garnish
with parsley and lemon slices.