Complex sentence: It is currently produced in the Midland Road factory in Worcester that Lea and Perrins built while a subsidiary in New Jersey, United States manufactures a US version of the recipe (which they say is based on authentic Indian recipes).
Split into simpler sentences: It is currently produced in the Midland Road factory in Worcester that Lea and Perrins built. A subsidiary in New Jersey, US, manufactures a US version of the recipe (which they say is based on authentic Indian recipes).