Place flour on a plate. Beat eggs gently, in a shallow bowl, until blended. In another shallow bowl, mix Panko bread crumbs, Italian seasoning, onion powder, salt and pepper.
Preheat large saute pan on medium-high 2-3 minutes. Dip patties in flour (coating both sides), then dip in egg mixture, allowing excess to drip off. Finally, dip into Panko bread crumb mixture.
Place oil in pan; swirl to coat. Add patties to pan and cook 2-3 minutes on each side to brown.
Reduce heat to medium; cook 2-3 more minutes on each side, until cooked through.
Meanwhile, combine sauce mix and milk in a medium saucepan. Bring to a boil on medium-high heat. Reduce heat to low; stir in butter and spinach. Cook 2-3 minutes, stirring often, or until spinach is wilted. Serve sauce over patties.