1 can (14 ounces) reduced-sodium whole tomatoes, undrained, cut up
1 teaspoon dried thyme leaves
1 cup frozen peas
1 pound flounder fillets, cut into 3/4-inch cubes
4 teaspoons lemon juice
Salt and pepper to taste
Heat oil in large saucpan over medium-high heat; add annatto seeds and saute for 3 minutes. Remove seeds with slotted spoon and discard. Add onion to saucepan; saute 2 minutes.
Add broth, potato, tomatoes and liquid, and thyme. Heat to boiling; reduce heat and simmer, covered, until potato is tender, about 10 minutes. Using potato masher or kitchen fork, coarsely mash mixture in pan.
Add peas and flounder; simmer until fish is tender and flakes with a fork, about 10 minutes. Stir in lemon juice; season to taste with salt and pepper.