Place meat and onions in a large crock-pot.

In a bowl combine mustard, paprika, brown sugar, and salt.

Combine Worcestershire sauce, vinegar, ketchup; add to mustard mixture; add to meat; add 2 cups of the water; stir; cover.

Cook on low for 8-10 hours, or high for 6 hours until meat is tender.

Blend flour with the remaining cup of water; add to meat mixture; stir until thickened.

Cook noodles until tender; drain.

Serve meat mixture over noodles.