Place water in a large pan; simmer. Add chicken, cover, and cook until no longer pink, about 15-20 minutes. Shred when cool.
STEP 2
Melt butter in a large pot. Stir in flour to form a paste; cook roux for 2 minutes. Add evaporated milk; stir to combine. Add broth and bring to a boil.
STEP 3
Add potatoes, carrots, bouillon, pepper, and salt. Cook until vegetables are tender, about 20 minutes.
STEP 4
Stir in chicken, peas, and corn. Cook until heated through, about 5 more minutes.