The original recipe called for scrod, but that isn't readily available fresh where I live. I've found that amberjack, redfish, or red snapper work nicely. Tilapia will work too, but try and find thicker pieces.
Saute mushrooms and garlic in 1 tbsp melted butter and olive oil in a large skillet over medium-high heat, stirring constantly, until tender. Set aside, and keep warm.
Combine the cracker crumbs, Parmesan cheese, salt, basil, oregano, and garlic powder in a medium bowl; dredge the fillets in the crumb mixture.
Pour 3 tbsp melted butter into an 11 x 7 x 1 1/2 inch baking dish. Arrange fillets over butter, turning to coat both sides; sprinkle with paprika. Bake, uncovered at 350 degrees for 15 minutes.
Drizzle the Marsala evenly over the fillets, and bake 5 minutes or until the fish flakes easily when tested with a fork. Spoon the reserved mushroom mixture over the fillets and serve immediately. (I've added the mushrooms before drizzling the Marsala, and love the extra taste -- but you sacrifice the crispness of the cracker crumb mixture.).