Place sweetbreads in a large mixing bowl; cover with cold water. Set aside to soak for 1 hour. Drain well; remove and discard white membrane.
Place sweetbreads and water to cover in a medium Dutch oven. Add lemon juice and 1 teaspoon salt. Bring to a boil. Reduce heat, and simmer 20 minutes. Drain well, and rinse with cold water. Cool completely. Slice sweetbreads into 1- inch slices; set aside.
Melt butter in a heavy skillet over medium heat. Add sweetbreads; cook slowly for 10 minutes or until browned. Add sherry, pepper, onion powder, and remaining salt; cover and simmer 5 minutes. Add cream; simmer 15 minutes.
Combine Hour and 1/4 cup water; stir until smooth. Add flour mixture to sweetbreads mixture; simmer until thickened, stirring occasionally. Spoon over toast points; sprinkle with paprika, and serve.