Cook the frozen spinach according to package directions. Drain thoroughly and mix in the parmesan cheese. Set aside and keep warm. In a medium saucepan, heat the canola oil margarine and stir in flour, Meanwhile whisk together milk and 3 more Tbsp. flour. When flour and oil form a paste, stir in milk mixture and bring very slowly to a boil, stirring carefully so the milk does not burn. Begin bringing water for poaching eggs to boil in large deep skillet. When sauce begins to thicken, gradually stir in grated cheddar a few Tbsp. at a time. Reduced fat cheese does not melt as readily as full-fat cheese, so go slow. Season sauce to taste with salt and white pepper. Poach the eggs in the boiling water in the skillet for approximately 2 minutes. While they are poaching: Mound 1/2 the spinach on each serving plate. Make an impression in each serving for the eggs. Remove poached eggs with slotted spoon, drain thoroughly, and nestle in spinach. Ladle cheese sauce over eggs and spinach. Serve this dish with toasted french bread rounds and a crisp green salad.