Line a baking sheet with foil then place a wire cooling rack on the baking sheet. Coat the wire rack with cooking spray.
Place the flour on a plate. Season well with sea salt, freshly cracked pepper, and garlic powder, to taste. Mix well.
Crack eggs in a shallow dish; beat until well combined.
Pour the Italian-seasoned panko and Parmesan on a plate and mix well.
Lightly dredge the portobello fries in the flour mixture; dip in the egg mixture; followed by coating evenly in the panko crumbs.
Place on the prepared baking racks. Repeat with remaining portobello fries.
Place the baking sheet in the refrigerator for 15-20 minutes. Side Note: This step makes the panko stick to the mushroom better.
Preheat the oven to 425 degrees–I used the convection setting.
Place the baking sheet in the oven and cook, until golden brown, about 9-12 minutes. Side Note: If you are not using the convection setting on your oven, flip the fries over halfway through cooking time.
Serve the portobello fries with warm Boursin cheese and warmed marinara sauce on the side as dipping sauces. Enjoy.