RINSE pinto beans; PLACE in large pan with 6 cups water; BRING to boiling,REDUCE heat and SIMMER 2 minutes2REMOVE from heat; COVER; let stand 1 hour3ADD beef, ham hock, onion salt, pepper, and thyme to pinto beans4BRING mixture to boilingREDUCE heat and simmer, covered 1 1/2 hours, STIRRING occasionally5REMOVE bones to cool; CUT off meat and DICEDISCARD bones6ADD meat, diced potatoes, and sliced carrots to soup7COVER; SIMMER the soup 30 minutes more.