Place unopened package of frozen fish into large pan; add cold water to cover package. Let stand until fish fillets are partially thawed, about 20 minutes. Cut fillets into bite-size chunks; set aside.

Cut bacon into 1-inch pieces; thinly slice onion. Drain potatoes; cut each potato in half.

In 2-quart saucepan over medium heat, cook bacon until just limp; add onion and cook until onion is browned. Stir in potatoes, tomatoes with their liquid, catchup, Worcestershire, pepper and thyme; cook 5 minutes, stirring occasionally.

Add fish; cook about 10 minutes longer or until fish flakes easily when tested with a fork, stirring fish mixture often.