Heat the oil in a large stockpot over medium heat.
Add the veggies and seasonings and saute for 7 to 8 minutes, or until the vegetables begin to soften.
Stir in the chicken base. Add the chicken broth and cilantro, and cook for 10 to 12 minutes, or until the carrots are tender.
Add chicken and cook, stirring often, until the chowder is thick and the chicken is heated through.
Make roux: melt the butter in a skillet over medium heat. Add the flour and stir to combine. Cook, stirring frequently, for 3 to 4 minutes to cook the flour but don't brown. Ladle 1/2 cup of the hot liquid from the stockpot into the skillet, whisking constantly.
When the first 1/2 cup of liquid is incorporated, repeat with another 1 cup of liquid, 1/2 at a time.
Pour the mixture into the stockpot, whisking to blend.
Cook, stirring frequently, for 3 to 5 minutes longer, or until the mixture begins to thicken. Remove the pot from the heat. Stir in the hot sauce, then the half and half, and serve.