Preheat oven to 400 F. Spray the insides of 6 one cup ramekins or souffle cups with cooking oil spray and sprinkle the bread crumbs inside. Tilt the dishes around to distribute the breadcrumbs all around. Place the cups on a baking sheet.
In a small pot, heat butter until melted. Add flour and stir until the mixture is bubbly and thick. Add milk gradually while stirring. The mixture will boil and thicken. Transfer to a large bowl and add the eggs, cheese and pepper. Stir everything well. Let cool.
Beat egg whites with an electric mixer until soft peaks form. Gently fold this into the yolk mixture in two additions. Once the mixture is uniform in color, pour them equally into the prepared cups.
Bake for 15 minutes, or until the tops are golden and puffy. Serve with the spinach sauce.
Microwave the spinach until wilted. Drain and squeeze out excess liquid. Using a blender or food processor, puree the spinach until smooth. Gradually add the cream and blend until the mixture is smooth. Season with salt and pepper, to taste.
Recipe adapted from Best Ever Recipes, a book published by John Wiley and Sons.