Set a large 6 to 8-quart sauce pot over medium heat. Add the butter, chopped onions, chopped bell pepper, cilantro, and garlic. Sauté the vegetables for 3-5 minutes to soften. Then add the chicken pieces, Sazon seasoning, chicken base, Rotel, and water to the pot. Stir well and push the chicken thighs down into the liquid.

Bring the liquid to a boil. Reduce the heat, just a little, and keep simmering for 20-25 minutes, until the chicken is cooked and the liquid has reduced by half.

Meanwhile, set out a small mixing bowl for the slaw. Combine the slaw mix, lime juice, and a pinch of salt. Toss well to coat. Then slice the tomatoes, cucumbers, and radishes very thin.

Use tongs to take the chicken thighs out of the pot. Place them on a cutting board. Use two forks to shred the chicken thighs into small chunks.

With an immersion blender, purée the remaining ingredients into a thick sauce. *If you don't have an immersion blender, you can also pour the ingredients into a standard blender. Carefully open the vent and purée until smooth. Pour the sauce back into the pot.

Place the shredded chicken back into the pot. Stir well to cook the chicken in the sauce.

To Assemble: Place one large romaine leaf in each hoagie roll to act as a liner for the bread. This chicken is extra saucy! Arrange slices of tomato, radishes, and cucumbers around the sides of the lettuce leaves. Scoop the chicken into the Romaine leaves. Top with fresh cabbage slaw and serve hot!