Cook spinach and drain, reserving the liquid until you have 1/2 cup. Melt butter in heavy pan, add flour, stirring until bpended and smooth, but not brown. Add onion and cook until soft, but do not brown. Combine milk and spinach liquid. Add slowly, stirring constantly to avoid lumps. Cook until thickened. Add season ings and Velveeta, cut unto small cubes. Stir until melted. Combine with spinach. This may be served immediately or put into a casserole and topped with buttered breadcrumbs. The flavor is improved if the latter is done and kept in the refrigerator overnight. This may also be frozen.
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