Continue to simmer the stew uncovered for another 5 to 10 minutes, stirring occasionally, until the tilapia is opaque and flakes easily with a fork and the sauce has thickened slightly. Total cook time for the fish from frozen is usually 15 to 20 minutes, depending on thickness.
Taste the sauce and adjust the seasoning with more salt and pepper if needed. Stir in the lemon juice, if using, for a bright finish.
Ladle the hot fish stew into bowls, making sure everyone gets plenty of both fish and sauce. Serve right away while cozy and steamy, with your favorite bread or sides for dipping.
For picky eaters, you can break the tilapia into smaller pieces and serve it more like a chunky pasta sauce over noodles or rice; kids often like it better that way. If your family doesn’t love strong tomato flavor, use half marinara and half broth for a milder red sauce. You can also add a drained can of white beans or chickpeas to the sauce when you add the broth to stretch the stew for more servings and extra protein. For a little heat, stir in a pinch of red pepper flakes with the garlic. If you prefer a slightly creamier stew, swirl in a splash of heavy cream or half-and-half at the very end, just before serving. Food safety tips: Keep the tilapia frozen until you’re ready to cook and use it by the date on the package. It is safe to cook tilapia directly from frozen as long as it reaches an internal temperature of 145°F (63°C) in the thickest part; if you’re unsure, use an instant-read thermometer. Make sure the stew returns to a good simmer after adding the frozen fillets, and adjust the cooking time if the fillets are especially thick. Refrigerate leftovers within 2 hours in a shallow container and use within 2 days; reheat gently on the stovetop until steaming hot all the way through, and avoid reheating more than once for best quality.
